From 84adefa331c4159d432d22840663c38f155cd4c1 Mon Sep 17 00:00:00 2001 From: Erlang/OTP Date: Fri, 20 Nov 2009 14:54:40 +0000 Subject: The R13B03 release. --- lib/compiler/src/cerl.erl | 4438 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 4438 insertions(+) create mode 100644 lib/compiler/src/cerl.erl (limited to 'lib/compiler/src/cerl.erl') diff --git a/lib/compiler/src/cerl.erl b/lib/compiler/src/cerl.erl new file mode 100644 index 0000000000..74fc0878cf --- /dev/null +++ b/lib/compiler/src/cerl.erl @@ -0,0 +1,4438 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2001-2009. All Rights Reserved. +%% +%% The contents of this file are subject to the Erlang Public License, +%% Version 1.1, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Erlang Public License along with this software. If not, it can be +%% retrieved online at http://www.erlang.org/. +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and limitations +%% under the License. +%% +%% %CopyrightEnd% + +%% ===================================================================== +%% @doc Core Erlang abstract syntax trees. +%% +%%

This module defines an abstract data type for representing Core +%% Erlang source code as syntax trees.

+%% +%%

A recommended starting point for the first-time user is the +%% documentation of the function type/1.

+%% +%%

NOTES:

+%% +%%

This module deals with the composition and decomposition of +%% syntactic entities (as opposed to semantic ones); its +%% purpose is to hide all direct references to the data structures +%% used to represent these entities. With few exceptions, the +%% functions in this module perform no semantic interpretation of +%% their inputs, and in general, the user is assumed to pass +%% type-correct arguments - if this is not done, the effects are not +%% defined.

+%% +%%

Currently, the internal data structure used is the same as +%% the record-based data structures used traditionally in the Beam +%% compiler.

+%% +%%

The internal representations of abstract syntax trees are +%% subject to change without notice, and should not be documented +%% outside this module. Furthermore, we do not give any guarantees on +%% how an abstract syntax tree may or may not be represented, with +%% the following exceptions: no syntax tree is represented by a +%% single atom, such as none, by a list constructor +%% [X | Y], or by the empty list []. This +%% can be relied on when writing functions that operate on syntax +%% trees.

+%% +%% @type cerl(). An abstract Core Erlang syntax tree. +%% +%%

Every abstract syntax tree has a type, given by the +%% function type/1. In addition, +%% each syntax tree has a list of user annotations (cf. get_ann/1), which are included +%% in the Core Erlang syntax.

+ +-module(cerl). + +-export([abstract/1, add_ann/2, alias_pat/1, alias_var/1, + ann_abstract/2, ann_c_alias/3, ann_c_apply/3, ann_c_atom/2, + ann_c_call/4, ann_c_case/3, ann_c_catch/2, ann_c_char/2, + ann_c_clause/3, ann_c_clause/4, ann_c_cons/3, ann_c_float/2, + ann_c_fname/3, ann_c_fun/3, ann_c_int/2, ann_c_let/4, + ann_c_letrec/3, ann_c_module/4, ann_c_module/5, ann_c_nil/1, + ann_c_cons_skel/3, ann_c_tuple_skel/2, ann_c_primop/3, + ann_c_receive/2, ann_c_receive/4, ann_c_seq/3, ann_c_string/2, + ann_c_try/6, ann_c_tuple/2, ann_c_values/2, ann_c_var/2, + ann_make_data/3, ann_make_list/2, ann_make_list/3, + ann_make_data_skel/3, ann_make_tree/3, apply_args/1, + apply_arity/1, apply_op/1, atom_lit/1, atom_name/1, atom_val/1, + c_alias/2, c_apply/2, c_atom/1, c_call/3, c_case/2, c_catch/1, + c_char/1, c_clause/2, c_clause/3, c_cons/2, c_float/1, + c_fname/2, c_fun/2, c_int/1, c_let/3, c_letrec/2, c_module/3, + c_module/4, c_nil/0, c_cons_skel/2, c_tuple_skel/1, c_primop/2, + c_receive/1, c_receive/3, c_seq/2, c_string/1, c_try/5, + c_tuple/1, c_values/1, c_var/1, call_args/1, call_arity/1, + call_module/1, call_name/1, case_arg/1, case_arity/1, + case_clauses/1, catch_body/1, char_lit/1, char_val/1, + clause_arity/1, clause_body/1, clause_guard/1, clause_pats/1, + clause_vars/1, concrete/1, cons_hd/1, cons_tl/1, copy_ann/2, + data_arity/1, data_es/1, data_type/1, float_lit/1, float_val/1, + fname_arity/1, fname_id/1, fold_literal/1, from_records/1, + fun_arity/1, fun_body/1, fun_vars/1, get_ann/1, int_lit/1, + int_val/1, is_c_alias/1, is_c_apply/1, is_c_atom/1, + is_c_call/1, is_c_case/1, is_c_catch/1, is_c_char/1, + is_c_clause/1, is_c_cons/1, is_c_float/1, is_c_fname/1, + is_c_fun/1, is_c_int/1, is_c_let/1, is_c_letrec/1, is_c_list/1, + is_c_module/1, is_c_nil/1, is_c_primop/1, is_c_receive/1, + is_c_seq/1, is_c_string/1, is_c_try/1, is_c_tuple/1, + is_c_values/1, is_c_var/1, is_data/1, is_leaf/1, is_literal/1, + is_literal_term/1, is_print_char/1, is_print_string/1, + let_arg/1, let_arity/1, let_body/1, let_vars/1, letrec_body/1, + letrec_defs/1, letrec_vars/1, list_elements/1, list_length/1, + make_data/2, make_list/1, make_list/2, make_data_skel/2, + make_tree/2, meta/1, module_attrs/1, module_defs/1, + module_exports/1, module_name/1, module_vars/1, + pat_list_vars/1, pat_vars/1, primop_args/1, primop_arity/1, + primop_name/1, receive_action/1, receive_clauses/1, + receive_timeout/1, seq_arg/1, seq_body/1, set_ann/2, + string_lit/1, string_val/1, subtrees/1, to_records/1, + try_arg/1, try_body/1, try_vars/1, try_evars/1, try_handler/1, + tuple_arity/1, tuple_es/1, type/1, unfold_literal/1, + update_c_alias/3, update_c_apply/3, update_c_call/4, + update_c_case/3, update_c_catch/2, update_c_clause/4, + update_c_cons/3, update_c_cons_skel/3, update_c_fname/2, + update_c_fname/3, update_c_fun/3, update_c_let/4, + update_c_letrec/3, update_c_module/5, update_c_primop/3, + update_c_receive/4, update_c_seq/3, update_c_try/6, + update_c_tuple/2, update_c_tuple_skel/2, update_c_values/2, + update_c_var/2, update_data/3, update_list/2, update_list/3, + update_data_skel/3, update_tree/2, update_tree/3, + values_arity/1, values_es/1, var_name/1, c_binary/1, + update_c_binary/2, ann_c_binary/2, is_c_binary/1, + binary_segments/1, c_bitstr/3, c_bitstr/4, c_bitstr/5, + update_c_bitstr/5, update_c_bitstr/6, ann_c_bitstr/5, + ann_c_bitstr/6, is_c_bitstr/1, bitstr_val/1, bitstr_size/1, + bitstr_bitsize/1, bitstr_unit/1, bitstr_type/1, + bitstr_flags/1]). + +%% +%% needed by the include file below -- do not move +%% +-type var_name() :: integer() | atom() | {atom(), integer()}. + +-include("core_parse.hrl"). + +-type c_alias() :: #c_alias{}. +-type c_apply() :: #c_apply{}. +-type c_binary() :: #c_binary{}. +-type c_bitstr() :: #c_bitstr{}. +-type c_call() :: #c_call{}. +-type c_case() :: #c_case{}. +-type c_catch() :: #c_catch{}. +-type c_clause() :: #c_clause{}. +-type c_cons() :: #c_cons{}. +-type c_fun() :: #c_fun{}. +-type c_let() :: #c_let{}. +-type c_letrec() :: #c_letrec{}. +-type c_literal() :: #c_literal{}. +-type c_module() :: #c_module{}. +-type c_primop() :: #c_primop{}. +-type c_receive() :: #c_receive{}. +-type c_seq() :: #c_seq{}. +-type c_try() :: #c_try{}. +-type c_tuple() :: #c_tuple{}. +-type c_values() :: #c_values{}. +-type c_var() :: #c_var{}. + +-type cerl() :: c_alias() | c_apply() | c_binary() | c_bitstr() + | c_call() | c_case() | c_catch() | c_clause() | c_cons() + | c_fun() | c_let() | c_letrec() | c_literal() + | c_module() | c_primop() | c_receive() | c_seq() + | c_try() | c_tuple() | c_values() | c_var(). + +%% ===================================================================== +%% Representation (general) +%% +%% All nodes are represented by tuples of arity 2 or (generally) +%% greater, whose first element is an atom which uniquely identifies the +%% type of the node, and whose second element is a (proper) list of +%% annotation terms associated with the node - this is by default empty. +%% +%% For most node constructor functions, there are analogous functions +%% named 'ann_...', taking one extra argument 'As' (always the first +%% argument), specifying an annotation list at node creation time. +%% Similarly, there are also functions named 'update_...', taking one +%% extra argument 'Old', specifying a node from which all fields not +%% explicitly given as arguments should be copied (generally, this is +%% the annotation field only). +%% ===================================================================== + +%% @spec type(Node::cerl()) -> atom() +%% +%% @doc Returns the type tag of Node. Current node types +%% are: +%% +%%

+%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%% +%%
aliasapplybinarybitstrcallcasecatch
clauseconsfunletletrecliteralmodule
primopreceiveseqtrytuplevaluesvar

+%% +%%

Note: The name of the primary constructor function for a node +%% type is always the name of the type itself, prefixed by +%% "c_"; recognizer predicates are correspondingly +%% prefixed by "is_c_". Furthermore, to simplify +%% preservation of annotations (cf. get_ann/1), there are +%% analogous constructor functions prefixed by "ann_c_" +%% and "update_c_", for setting the annotation list of +%% the new node to either a specific value or to the annotations of an +%% existing node, respectively.

+%% +%% @see abstract/1 +%% @see c_alias/2 +%% @see c_apply/2 +%% @see c_binary/1 +%% @see c_bitstr/5 +%% @see c_call/3 +%% @see c_case/2 +%% @see c_catch/1 +%% @see c_clause/3 +%% @see c_cons/2 +%% @see c_fun/2 +%% @see c_let/3 +%% @see c_letrec/2 +%% @see c_module/3 +%% @see c_primop/2 +%% @see c_receive/1 +%% @see c_seq/2 +%% @see c_try/3 +%% @see c_tuple/1 +%% @see c_values/1 +%% @see c_var/1 +%% @see get_ann/1 +%% @see to_records/1 +%% @see from_records/1 +%% @see data_type/1 +%% @see subtrees/1 +%% @see meta/1 + +-type ctype() :: 'alias' | 'apply' | 'binary' | 'bitrst' | 'call' | 'case' + | 'catch' | 'clause' | 'cons' | 'fun' | 'let' | 'letrec' + | 'literal' | 'module' | 'primop' | 'receive' | 'seq' | 'try' + | 'tuple' | 'values' | 'var'. + +-spec type(cerl()) -> ctype(). + +type(#c_alias{}) -> alias; +type(#c_apply{}) -> apply; +type(#c_binary{}) -> binary; +type(#c_bitstr{}) -> bitstr; +type(#c_call{}) -> call; +type(#c_case{}) -> 'case'; +type(#c_catch{}) -> 'catch'; +type(#c_clause{}) -> clause; +type(#c_cons{}) -> cons; +type(#c_fun{}) -> 'fun'; +type(#c_let{}) -> 'let'; +type(#c_letrec{}) -> letrec; +type(#c_literal{}) -> literal; +type(#c_module{}) -> module; +type(#c_primop{}) -> primop; +type(#c_receive{}) -> 'receive'; +type(#c_seq{}) -> seq; +type(#c_try{}) -> 'try'; +type(#c_tuple{}) -> tuple; +type(#c_values{}) -> values; +type(#c_var{}) -> var. + + +%% @spec is_leaf(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is a leaf node, +%% otherwise false. The current leaf node types are +%% literal and var. +%% +%%

Note: all literals (cf. is_literal/1) are leaf +%% nodes, even if they represent structured (constant) values such as +%% {foo, [bar, baz]}. Also note that variables are leaf +%% nodes but not literals.

+%% +%% @see type/1 +%% @see is_literal/1 + +-spec is_leaf(cerl()) -> boolean(). + +is_leaf(Node) -> + case type(Node) of + literal -> true; + var -> true; + _ -> false + end. + + +%% @spec get_ann(cerl()) -> [term()] +%% +%% @doc Returns the list of user annotations associated with a syntax +%% tree node. For a newly created node, this is the empty list. The +%% annotations may be any terms. +%% +%% @see set_ann/2 + +-spec get_ann(cerl()) -> [term()]. + +get_ann(Node) -> + element(2, Node). + + +%% @spec set_ann(Node::cerl(), Annotations::[term()]) -> cerl() +%% +%% @doc Sets the list of user annotations of Node to +%% Annotations. +%% +%% @see get_ann/1 +%% @see add_ann/2 +%% @see copy_ann/2 + +-spec set_ann(cerl(), [term()]) -> cerl(). + +set_ann(Node, List) -> + setelement(2, Node, List). + + +%% @spec add_ann(Annotations::[term()], Node::cerl()) -> cerl() +%% +%% @doc Appends Annotations to the list of user +%% annotations of Node. +%% +%%

Note: this is equivalent to set_ann(Node, Annotations ++ +%% get_ann(Node)), but potentially more efficient.

+%% +%% @see get_ann/1 +%% @see set_ann/2 + +-spec add_ann([term()], cerl()) -> cerl(). + +add_ann(Terms, Node) -> + set_ann(Node, Terms ++ get_ann(Node)). + + +%% @spec copy_ann(Source::cerl(), Target::cerl()) -> cerl() +%% +%% @doc Copies the list of user annotations from Source +%% to Target. +%% +%%

Note: this is equivalent to set_ann(Target, +%% get_ann(Source)), but potentially more efficient.

+%% +%% @see get_ann/1 +%% @see set_ann/2 + +-spec copy_ann(cerl(), cerl()) -> cerl(). + +copy_ann(Source, Target) -> + set_ann(Target, get_ann(Source)). + + +%% @spec abstract(Term::term()) -> cerl() +%% +%% @doc Creates a syntax tree corresponding to an Erlang term. +%% Term must be a literal term, i.e., one that can be +%% represented as a source code literal. Thus, it may not contain a +%% process identifier, port, reference, binary or function value as a +%% subterm. +%% +%%

Note: This is a constant time operation.

+%% +%% @see ann_abstract/2 +%% @see concrete/1 +%% @see is_literal/1 +%% @see is_literal_term/1 + +-spec abstract(term()) -> c_literal(). + +abstract(T) -> + #c_literal{val = T}. + + +%% @spec ann_abstract(Annotations::[term()], Term::term()) -> cerl() +%% @see abstract/1 + +-spec ann_abstract([term()], term()) -> c_literal(). + +ann_abstract(As, T) -> + #c_literal{val = T, anno = As}. + + +%% @spec is_literal_term(Term::term()) -> boolean() +%% +%% @doc Returns true if Term can be +%% represented as a literal, otherwise false. This +%% function takes time proportional to the size of Term. +%% +%% @see abstract/1 + +-spec is_literal_term(term()) -> boolean(). + +is_literal_term(T) when is_integer(T) -> true; +is_literal_term(T) when is_float(T) -> true; +is_literal_term(T) when is_atom(T) -> true; +is_literal_term([]) -> true; +is_literal_term([H | T]) -> + is_literal_term(H) andalso is_literal_term(T); +is_literal_term(T) when is_tuple(T) -> + is_literal_term_list(tuple_to_list(T)); +is_literal_term(B) when is_bitstring(B) -> true; +is_literal_term(_) -> + false. + +-spec is_literal_term_list([term()]) -> boolean(). + +is_literal_term_list([T | Ts]) -> + case is_literal_term(T) of + true -> + is_literal_term_list(Ts); + false -> + false + end; +is_literal_term_list([]) -> + true. + + +%% @spec concrete(Node::cerl()) -> term() +%% +%% @doc Returns the Erlang term represented by a syntax tree. An +%% exception is thrown if Node does not represent a +%% literal term. +%% +%%

Note: This is a constant time operation.

+%% +%% @see abstract/1 +%% @see is_literal/1 + +%% Because the normal tuple and list constructor operations always +%% return a literal if the arguments are literals, 'concrete' and +%% 'is_literal' never need to traverse the structure. + +-spec concrete(c_literal()) -> term(). + +concrete(#c_literal{val = V}) -> + V. + + +%% @spec is_literal(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents a +%% literal term, otherwise false. This function returns +%% true if and only if the value of +%% concrete(Node) is defined. +%% +%%

Note: This is a constant time operation.

+%% +%% @see abstract/1 +%% @see concrete/1 +%% @see fold_literal/1 + +-spec is_literal(cerl()) -> boolean(). + +is_literal(#c_literal{}) -> + true; +is_literal(_) -> + false. + + +%% @spec fold_literal(Node::cerl()) -> cerl() +%% +%% @doc Assures that literals have a compact representation. This is +%% occasionally useful if c_cons_skel/2, +%% c_tuple_skel/1 or unfold_literal/1 were +%% used in the construction of Node, and you want to revert +%% to the normal "folded" representation of literals. If +%% Node represents a tuple or list constructor, its +%% elements are rewritten recursively, and the node is reconstructed +%% using c_cons/2 or c_tuple/1, respectively; +%% otherwise, Node is not changed. +%% +%% @see is_literal/1 +%% @see c_cons_skel/2 +%% @see c_tuple_skel/1 +%% @see c_cons/2 +%% @see c_tuple/1 +%% @see unfold_literal/1 + +-spec fold_literal(cerl()) -> cerl(). + +fold_literal(Node) -> + case type(Node) of + tuple -> + update_c_tuple(Node, fold_literal_list(tuple_es(Node))); + cons -> + update_c_cons(Node, fold_literal(cons_hd(Node)), + fold_literal(cons_tl(Node))); + _ -> + Node + end. + +fold_literal_list([E | Es]) -> + [fold_literal(E) | fold_literal_list(Es)]; +fold_literal_list([]) -> + []. + + +%% @spec unfold_literal(Node::cerl()) -> cerl() +%% +%% @doc Assures that literals have a fully expanded representation. If +%% Node represents a literal tuple or list constructor, its +%% elements are rewritten recursively, and the node is reconstructed +%% using c_cons_skel/2 or c_tuple_skel/1, +%% respectively; otherwise, Node is not changed. The {@link +%% fold_literal/1} can be used to revert to the normal compact +%% representation. +%% +%% @see is_literal/1 +%% @see c_cons_skel/2 +%% @see c_tuple_skel/1 +%% @see c_cons/2 +%% @see c_tuple/1 +%% @see fold_literal/1 + +-spec unfold_literal(cerl()) -> cerl(). + +unfold_literal(Node) -> + case type(Node) of + literal -> + copy_ann(Node, unfold_concrete(concrete(Node))); + _ -> + Node + end. + +unfold_concrete(Val) -> + case Val of + _ when is_tuple(Val) -> + c_tuple_skel(unfold_concrete_list(tuple_to_list(Val))); + [H|T] -> + c_cons_skel(unfold_concrete(H), unfold_concrete(T)); + _ -> + abstract(Val) + end. + +unfold_concrete_list([E | Es]) -> + [unfold_concrete(E) | unfold_concrete_list(Es)]; +unfold_concrete_list([]) -> + []. + + +%% --------------------------------------------------------------------- + +%% @spec c_module(Name::cerl(), Exports, Definitions) -> cerl() +%% +%% Exports = [cerl()] +%% Definitions = [{cerl(), cerl()}] +%% +%% @equiv c_module(Name, Exports, [], Definitions) + +-spec c_module(cerl(), [cerl()], [{cerl(), cerl()}]) -> c_module(). + +c_module(Name, Exports, Es) -> + #c_module{name = Name, exports = Exports, attrs = [], defs = Es}. + + +%% @spec c_module(Name::cerl(), Exports, Attributes, Definitions) -> +%% cerl() +%% +%% Exports = [cerl()] +%% Attributes = [{cerl(), cerl()}] +%% Definitions = [{cerl(), cerl()}] +%% +%% @doc Creates an abstract module definition. The result represents +%% 
+%%   module Name [E1, ..., Ek]
+%%     attributes [K1 = T1, ...,
+%%                 Km = Tm]
+%%     V1 = F1
+%%     ...
+%%     Vn = Fn
+%%   end
+%% +%% if Exports = [E1, ..., Ek], +%% Attributes = [{K1, T1}, ..., {Km, Tm}], +%% and Definitions = [{V1, F1}, ..., {Vn, +%% Fn}]. +%% +%%

Name and all the Ki must be atom +%% literals, and all the Ti must be constant literals. All +%% the Vi and Ei must have type +%% var and represent function names. All the +%% Fi must have type 'fun'.

+%% +%% @see c_module/3 +%% @see module_name/1 +%% @see module_exports/1 +%% @see module_attrs/1 +%% @see module_defs/1 +%% @see module_vars/1 +%% @see ann_c_module/4 +%% @see ann_c_module/5 +%% @see update_c_module/5 +%% @see c_atom/1 +%% @see c_var/1 +%% @see c_fun/2 +%% @see is_literal/1 + +-spec c_module(cerl(), [cerl()], [{cerl(), cerl()}], [{cerl(), cerl()}]) -> + c_module(). + +c_module(Name, Exports, Attrs, Es) -> + #c_module{name = Name, exports = Exports, attrs = Attrs, defs = Es}. + + +%% @spec ann_c_module(As::[term()], Name::cerl(), Exports, +%% Definitions) -> cerl() +%% +%% Exports = [cerl()] +%% Definitions = [{cerl(), cerl()}] +%% +%% @see c_module/3 +%% @see ann_c_module/5 + +-spec ann_c_module([term()], cerl(), [cerl()], [{cerl(), cerl()}]) -> + c_module(). + +ann_c_module(As, Name, Exports, Es) -> + #c_module{name = Name, exports = Exports, attrs = [], defs = Es, + anno = As}. + + +%% @spec ann_c_module(As::[term()], Name::cerl(), Exports, +%% Attributes, Definitions) -> cerl() +%% +%% Exports = [cerl()] +%% Attributes = [{cerl(), cerl()}] +%% Definitions = [{cerl(), cerl()}] +%% +%% @see c_module/4 +%% @see ann_c_module/4 + +-spec ann_c_module([term()], cerl(), [cerl()], + [{cerl(), cerl()}], [{cerl(), cerl()}]) -> c_module(). + +ann_c_module(As, Name, Exports, Attrs, Es) -> + #c_module{name = Name, exports = Exports, attrs = Attrs, defs = Es, + anno = As}. + + +%% @spec update_c_module(Old::cerl(), Name::cerl(), Exports, +%% Attributes, Definitions) -> cerl() +%% +%% Exports = [cerl()] +%% Attributes = [{cerl(), cerl()}] +%% Definitions = [{cerl(), cerl()}] +%% +%% @see c_module/4 + +-spec update_c_module(c_module(), cerl(), [cerl()], + [{cerl(), cerl()}], [{cerl(), cerl()}]) -> c_module(). + +update_c_module(Node, Name, Exports, Attrs, Es) -> + #c_module{name = Name, exports = Exports, attrs = Attrs, defs = Es, + anno = get_ann(Node)}. + + +%% @spec is_c_module(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% module definition, otherwise false. +%% +%% @see type/1 + +-spec is_c_module(cerl()) -> boolean(). + +is_c_module(#c_module{}) -> + true; +is_c_module(_) -> + false. + + +%% @spec module_name(Node::cerl()) -> cerl() +%% +%% @doc Returns the name subtree of an abstract module definition. +%% +%% @see c_module/4 + +-spec module_name(c_module()) -> cerl(). + +module_name(Node) -> + Node#c_module.name. + + +%% @spec module_exports(Node::cerl()) -> [cerl()] +%% +%% @doc Returns the list of exports subtrees of an abstract module +%% definition. +%% +%% @see c_module/4 + +-spec module_exports(c_module()) -> [cerl()]. + +module_exports(Node) -> + Node#c_module.exports. + + +%% @spec module_attrs(Node::cerl()) -> [{cerl(), cerl()}] +%% +%% @doc Returns the list of pairs of attribute key/value subtrees of +%% an abstract module definition. +%% +%% @see c_module/4 + +-spec module_attrs(c_module()) -> [{cerl(), cerl()}]. + +module_attrs(Node) -> + Node#c_module.attrs. + + +%% @spec module_defs(Node::cerl()) -> [{cerl(), cerl()}] +%% +%% @doc Returns the list of function definitions of an abstract module +%% definition. +%% +%% @see c_module/4 + +-spec module_defs(c_module()) -> [{cerl(), cerl()}]. + +module_defs(Node) -> + Node#c_module.defs. + + +%% @spec module_vars(Node::cerl()) -> [cerl()] +%% +%% @doc Returns the list of left-hand side function variable subtrees +%% of an abstract module definition. +%% +%% @see c_module/4 + +-spec module_vars(c_module()) -> [cerl()]. + +module_vars(Node) -> + [F || {F, _} <- module_defs(Node)]. + + +%% --------------------------------------------------------------------- + +%% @spec c_int(Value::integer()) -> cerl() +%% +%% @doc Creates an abstract integer literal. The lexical +%% representation is the canonical decimal numeral of +%% Value. +%% +%% @see ann_c_int/2 +%% @see is_c_int/1 +%% @see int_val/1 +%% @see int_lit/1 +%% @see c_char/1 + +-spec c_int(integer()) -> c_literal(). + +c_int(Value) -> + #c_literal{val = Value}. + + +%% @spec ann_c_int(As::[term()], Value::integer()) -> cerl() +%% @see c_int/1 + +-spec ann_c_int([term()], integer()) -> c_literal(). + +ann_c_int(As, Value) -> + #c_literal{val = Value, anno = As}. + + +%% @spec is_c_int(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents an +%% integer literal, otherwise false. +%% @see c_int/1 + +-spec is_c_int(cerl()) -> boolean(). + +is_c_int(#c_literal{val = V}) when is_integer(V) -> + true; +is_c_int(_) -> + false. + + +%% @spec int_val(cerl()) -> integer() +%% +%% @doc Returns the value represented by an integer literal node. +%% @see c_int/1 + +-spec int_val(c_literal()) -> integer(). + +int_val(Node) -> + Node#c_literal.val. + + +%% @spec int_lit(cerl()) -> string() +%% +%% @doc Returns the numeral string represented by an integer literal +%% node. +%% @see c_int/1 + +-spec int_lit(c_literal()) -> string(). + +int_lit(Node) -> + integer_to_list(int_val(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_float(Value::float()) -> cerl() +%% +%% @doc Creates an abstract floating-point literal. The lexical +%% representation is the decimal floating-point numeral of +%% Value. +%% +%% @see ann_c_float/2 +%% @see is_c_float/1 +%% @see float_val/1 +%% @see float_lit/1 + +%% Note that not all floating-point numerals can be represented with +%% full precision. + +-spec c_float(float()) -> c_literal(). + +c_float(Value) -> + #c_literal{val = Value}. + + +%% @spec ann_c_float(As::[term()], Value::float()) -> cerl() +%% @see c_float/1 + +-spec ann_c_float([term()], float()) -> c_literal(). + +ann_c_float(As, Value) -> + #c_literal{val = Value, anno = As}. + + +%% @spec is_c_float(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents a +%% floating-point literal, otherwise false. +%% @see c_float/1 + +-spec is_c_float(cerl()) -> boolean(). + +is_c_float(#c_literal{val = V}) when is_float(V) -> + true; +is_c_float(_) -> + false. + + +%% @spec float_val(cerl()) -> float() +%% +%% @doc Returns the value represented by a floating-point literal +%% node. +%% @see c_float/1 + +-spec float_val(c_literal()) -> float(). + +float_val(Node) -> + Node#c_literal.val. + + +%% @spec float_lit(cerl()) -> string() +%% +%% @doc Returns the numeral string represented by a floating-point +%% literal node. +%% @see c_float/1 + +-spec float_lit(c_literal()) -> string(). + +float_lit(Node) -> + float_to_list(float_val(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_atom(Name) -> cerl() +%% Name = atom() | string() +%% +%% @doc Creates an abstract atom literal. The print name of the atom +%% is the character sequence represented by Name. +%% +%%

Note: passing a string as argument to this function causes a +%% corresponding atom to be created for the internal representation.

+%% +%% @see ann_c_atom/2 +%% @see is_c_atom/1 +%% @see atom_val/1 +%% @see atom_name/1 +%% @see atom_lit/1 + +-spec c_atom(atom() | string()) -> c_literal(). + +c_atom(Name) when is_atom(Name) -> + #c_literal{val = Name}; +c_atom(Name) -> + #c_literal{val = list_to_atom(Name)}. + + +%% @spec ann_c_atom(As::[term()], Name) -> cerl() +%% Name = atom() | string() +%% @see c_atom/1 + +-spec ann_c_atom([term()], atom() | string()) -> c_literal(). + +ann_c_atom(As, Name) when is_atom(Name) -> + #c_literal{val = Name, anno = As}; +ann_c_atom(As, Name) -> + #c_literal{val = list_to_atom(Name), anno = As}. + + +%% @spec is_c_atom(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents an +%% atom literal, otherwise false. +%% +%% @see c_atom/1 + +-spec is_c_atom(cerl()) -> boolean(). + +is_c_atom(#c_literal{val = V}) when is_atom(V) -> + true; +is_c_atom(_) -> + false. + +%% @spec atom_val(cerl()) -> atom() +%% +%% @doc Returns the value represented by an abstract atom. +%% +%% @see c_atom/1 + +-spec atom_val(c_literal()) -> atom(). + +atom_val(Node) -> + Node#c_literal.val. + + +%% @spec atom_name(cerl()) -> string() +%% +%% @doc Returns the printname of an abstract atom. +%% +%% @see c_atom/1 + +-spec atom_name(c_literal()) -> string(). + +atom_name(Node) -> + atom_to_list(atom_val(Node)). + + +%% @spec atom_lit(cerl()) -> string() +%% +%% @doc Returns the literal string represented by an abstract +%% atom. This always includes surrounding single-quote characters. +%% +%%

Note that an abstract atom may have several literal +%% representations, and that the representation yielded by this +%% function is not fixed; e.g., +%% atom_lit(c_atom("a\012b")) could yield the string +%% "\'a\\nb\'".

+%% +%% @see c_atom/1 + +%% TODO: replace the use of the unofficial 'write_string/2'. + +-spec atom_lit(cerl()) -> string(). + +atom_lit(Node) -> + io_lib:write_string(atom_name(Node), $'). %' stupid Emacs. + + +%% --------------------------------------------------------------------- + +%% @spec c_char(Value) -> cerl() +%% +%% Value = char() | integer() +%% +%% @doc Creates an abstract character literal. If the local +%% implementation of Erlang defines char() as a subset of +%% integer(), this function is equivalent to +%% c_int/1. Otherwise, if the given value is an integer, +%% it will be converted to the character with the corresponding +%% code. The lexical representation of a character is +%% "$Char", where Char is a single +%% printing character or an escape sequence. +%% +%% @see c_int/1 +%% @see c_string/1 +%% @see ann_c_char/2 +%% @see is_c_char/1 +%% @see char_val/1 +%% @see char_lit/1 +%% @see is_print_char/1 + +-spec c_char(non_neg_integer()) -> c_literal(). + +c_char(Value) when is_integer(Value), Value >= 0 -> + #c_literal{val = Value}. + + +%% @spec ann_c_char(As::[term()], Value::char()) -> cerl() +%% @see c_char/1 + +-spec ann_c_char([term()], char()) -> c_literal(). + +ann_c_char(As, Value) -> + #c_literal{val = Value, anno = As}. + + +%% @spec is_c_char(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node may represent a +%% character literal, otherwise false. +%% +%%

If the local implementation of Erlang defines +%% char() as a subset of integer(), then +%% is_c_int(Node) will also yield +%% true.

+%% +%% @see c_char/1 +%% @see is_print_char/1 + +-spec is_c_char(c_literal()) -> boolean(). + +is_c_char(#c_literal{val = V}) when is_integer(V), V >= 0 -> + is_char_value(V); +is_c_char(_) -> + false. + + +%% @spec is_print_char(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node may represent a +%% "printing" character, otherwise false. (Cf. +%% is_c_char/1.) A "printing" character has either a +%% given graphical representation, or a "named" escape sequence such +%% as "\n". Currently, only ISO 8859-1 (Latin-1) +%% character values are recognized. +%% +%% @see c_char/1 +%% @see is_c_char/1 + +-spec is_print_char(cerl()) -> boolean(). + +is_print_char(#c_literal{val = V}) when is_integer(V), V >= 0 -> + is_print_char_value(V); +is_print_char(_) -> + false. + + +%% @spec char_val(cerl()) -> char() +%% +%% @doc Returns the value represented by an abstract character literal. +%% +%% @see c_char/1 + +-spec char_val(c_literal()) -> char(). + +char_val(Node) -> + Node#c_literal.val. + + +%% @spec char_lit(cerl()) -> string() +%% +%% @doc Returns the literal string represented by an abstract +%% character. This includes a leading $ +%% character. Currently, all characters that are not in the set of ISO +%% 8859-1 (Latin-1) "printing" characters will be escaped. +%% +%% @see c_char/1 + +-spec char_lit(c_literal()) -> string(). + +char_lit(Node) -> + io_lib:write_char(char_val(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_string(Value::string()) -> cerl() +%% +%% @doc Creates an abstract string literal. Equivalent to creating an +%% abstract list of the corresponding character literals +%% (cf. is_c_string/1), but is typically more +%% efficient. The lexical representation of a string is +%% ""Chars"", where Chars is a +%% sequence of printing characters or spaces. +%% +%% @see c_char/1 +%% @see ann_c_string/2 +%% @see is_c_string/1 +%% @see string_val/1 +%% @see string_lit/1 +%% @see is_print_string/1 + +-spec c_string(string()) -> c_literal(). + +c_string(Value) -> + #c_literal{val = Value}. + + +%% @spec ann_c_string(As::[term()], Value::string()) -> cerl() +%% @see c_string/1 + +-spec ann_c_string([term()], string()) -> c_literal(). + +ann_c_string(As, Value) -> + #c_literal{val = Value, anno = As}. + + +%% @spec is_c_string(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node may represent a +%% string literal, otherwise false. Strings are defined +%% as lists of characters; see is_c_char/1 for details. +%% +%% @see c_string/1 +%% @see is_c_char/1 +%% @see is_print_string/1 + +-spec is_c_string(cerl()) -> boolean(). + +is_c_string(#c_literal{val = V}) -> + is_char_list(V); +is_c_string(_) -> + false. + + +%% @spec is_print_string(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node may represent a +%% string literal containing only "printing" characters, otherwise +%% false. See is_c_string/1 and +%% is_print_char/1 for details. Currently, only ISO +%% 8859-1 (Latin-1) character values are recognized. +%% +%% @see c_string/1 +%% @see is_c_string/1 +%% @see is_print_char/1 + +-spec is_print_string(cerl()) -> boolean(). + +is_print_string(#c_literal{val = V}) -> + is_print_char_list(V); +is_print_string(_) -> + false. + + +%% @spec string_val(cerl()) -> string() +%% +%% @doc Returns the value represented by an abstract string literal. +%% +%% @see c_string/1 + +-spec string_val(c_literal()) -> string(). + +string_val(Node) -> + Node#c_literal.val. + + +%% @spec string_lit(cerl()) -> string() +%% +%% @doc Returns the literal string represented by an abstract string. +%% This includes surrounding double-quote characters +%% "...". Currently, characters that are not in the set +%% of ISO 8859-1 (Latin-1) "printing" characters will be escaped, +%% except for spaces. +%% +%% @see c_string/1 + +-spec string_lit(c_literal()) -> string(). + +string_lit(Node) -> + io_lib:write_string(string_val(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_nil() -> cerl() +%% +%% @doc Creates an abstract empty list. The result represents +%% "[]". The empty list is traditionally called "nil". +%% +%% @see ann_c_nil/1 +%% @see is_c_list/1 +%% @see c_cons/2 + +-spec c_nil() -> c_literal(). + +c_nil() -> + #c_literal{val = []}. + + +%% @spec ann_c_nil(As::[term()]) -> cerl() +%% @see c_nil/0 + +-spec ann_c_nil([term()]) -> c_literal(). + +ann_c_nil(As) -> + #c_literal{val = [], anno = As}. + + +%% @spec is_c_nil(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% empty list, otherwise false. + +-spec is_c_nil(cerl()) -> boolean(). + +is_c_nil(#c_literal{val = []}) -> + true; +is_c_nil(_) -> + false. + + +%% --------------------------------------------------------------------- + +%% @spec c_cons(Head::cerl(), Tail::cerl()) -> cerl() +%% +%% @doc Creates an abstract list constructor. The result represents +%% "[Head | Tail]". Note that if both +%% Head and Tail have type +%% literal, then the result will also have type +%% literal, and annotations on Head and +%% Tail are lost. +%% +%%

Recall that in Erlang, the tail element of a list constructor is +%% not necessarily a list.

+%% +%% @see ann_c_cons/3 +%% @see update_c_cons/3 +%% @see c_cons_skel/2 +%% @see is_c_cons/1 +%% @see cons_hd/1 +%% @see cons_tl/1 +%% @see is_c_list/1 +%% @see c_nil/0 +%% @see list_elements/1 +%% @see list_length/1 +%% @see make_list/2 + +%% *Always* collapse literals. + +-spec c_cons(cerl(), cerl()) -> c_literal() | c_cons(). + +c_cons(#c_literal{val = Head}, #c_literal{val = Tail}) -> + #c_literal{val = [Head | Tail]}; +c_cons(Head, Tail) -> + #c_cons{hd = Head, tl = Tail}. + + +%% @spec ann_c_cons(As::[term()], Head::cerl(), Tail::cerl()) -> cerl() +%% @see c_cons/2 + +-spec ann_c_cons([term()], cerl(), cerl()) -> c_literal() | c_cons(). + +ann_c_cons(As, #c_literal{val = Head}, #c_literal{val = Tail}) -> + #c_literal{val = [Head | Tail], anno = As}; +ann_c_cons(As, Head, Tail) -> + #c_cons{hd = Head, tl = Tail, anno = As}. + + +%% @spec update_c_cons(Old::cerl(), Head::cerl(), Tail::cerl()) -> +%% cerl() +%% @see c_cons/2 + +-spec update_c_cons(c_literal() | c_cons(), cerl(), cerl()) -> + c_literal() | c_cons(). + +update_c_cons(Node, #c_literal{val = Head}, #c_literal{val = Tail}) -> + #c_literal{val = [Head | Tail], anno = get_ann(Node)}; +update_c_cons(Node, Head, Tail) -> + #c_cons{hd = Head, tl = Tail, anno = get_ann(Node)}. + + +%% @spec c_cons_skel(Head::cerl(), Tail::cerl()) -> cerl() +%% +%% @doc Creates an abstract list constructor skeleton. Does not fold +%% constant literals, i.e., the result always has type +%% cons, representing "[Head | +%% Tail]". +%% +%%

This function is occasionally useful when it is necessary to have +%% annotations on the subnodes of a list constructor node, even when the +%% subnodes are constant literals. Note however that +%% is_literal/1 will yield false and +%% concrete/1 will fail if passed the result from this +%% function.

+%% +%%

fold_literal/1 can be used to revert a node to the +%% normal-form representation.

+%% +%% @see ann_c_cons_skel/3 +%% @see update_c_cons_skel/3 +%% @see c_cons/2 +%% @see is_c_cons/1 +%% @see is_c_list/1 +%% @see c_nil/0 +%% @see is_literal/1 +%% @see fold_literal/1 +%% @see concrete/1 + +%% *Never* collapse literals. + +-spec c_cons_skel(cerl(), cerl()) -> c_cons(). + +c_cons_skel(Head, Tail) -> + #c_cons{hd = Head, tl = Tail}. + + +%% @spec ann_c_cons_skel(As::[term()], Head::cerl(), Tail::cerl()) -> +%% cerl() +%% @see c_cons_skel/2 + +-spec ann_c_cons_skel([term()], cerl(), cerl()) -> c_cons(). + +ann_c_cons_skel(As, Head, Tail) -> + #c_cons{hd = Head, tl = Tail, anno = As}. + + +%% @spec update_c_cons_skel(Old::cerl(), Head::cerl(), Tail::cerl()) -> +%% cerl() +%% @see c_cons_skel/2 + +-spec update_c_cons_skel(c_cons() | c_literal(), cerl(), cerl()) -> c_cons(). + +update_c_cons_skel(Node, Head, Tail) -> + #c_cons{hd = Head, tl = Tail, anno = get_ann(Node)}. + + +%% @spec is_c_cons(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% list constructor, otherwise false. + +-spec is_c_cons(cerl()) -> boolean(). + +is_c_cons(#c_cons{}) -> + true; +is_c_cons(#c_literal{val = [_ | _]}) -> + true; +is_c_cons(_) -> + false. + + +%% @spec cons_hd(cerl()) -> cerl() +%% +%% @doc Returns the head subtree of an abstract list constructor. +%% +%% @see c_cons/2 + +-spec cons_hd(c_cons() | c_literal()) -> cerl(). + +cons_hd(#c_cons{hd = Head}) -> + Head; +cons_hd(#c_literal{val = [Head | _]}) -> + #c_literal{val = Head}. + + +%% @spec cons_tl(cerl()) -> cerl() +%% +%% @doc Returns the tail subtree of an abstract list constructor. +%% +%%

Recall that the tail does not necessarily represent a proper +%% list.

+%% +%% @see c_cons/2 + +-spec cons_tl(c_cons() | c_literal()) -> cerl(). + +cons_tl(#c_cons{tl = Tail}) -> + Tail; +cons_tl(#c_literal{val = [_ | Tail]}) -> + #c_literal{val = Tail}. + + +%% @spec is_c_list(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents a +%% proper list, otherwise false. A proper list is either +%% the empty list [], or a cons cell [Head | +%% Tail], where recursively Tail is a +%% proper list. +%% +%%

Note: Because Node is a syntax tree, the actual +%% run-time values corresponding to its subtrees may often be partially +%% or completely unknown. Thus, if Node represents e.g. +%% "[... | Ns]" (where Ns is a variable), then +%% the function will return false, because it is not known +%% whether Ns will be bound to a list at run-time. If +%% Node instead represents e.g. "[1, 2, 3]" or +%% "[A | []]", then the function will return +%% true.

+%% +%% @see c_cons/2 +%% @see c_nil/0 +%% @see list_elements/1 +%% @see list_length/1 + +-spec is_c_list(cerl()) -> boolean(). + +is_c_list(#c_cons{tl = Tail}) -> + is_c_list(Tail); +is_c_list(#c_literal{val = V}) -> + is_proper_list(V); +is_c_list(_) -> + false. + +is_proper_list([_ | Tail]) -> + is_proper_list(Tail); +is_proper_list([]) -> + true; +is_proper_list(_) -> + false. + +%% @spec list_elements(cerl()) -> [cerl()] +%% +%% @doc Returns the list of element subtrees of an abstract list. +%% Node must represent a proper list. E.g., if +%% Node represents "[X1, X2 | +%% [X3, X4 | []]", then +%% list_elements(Node) yields the list [X1, X2, X3, +%% X4]. +%% +%% @see c_cons/2 +%% @see c_nil/1 +%% @see is_c_list/1 +%% @see list_length/1 +%% @see make_list/2 + +-spec list_elements(c_cons() | c_literal()) -> [cerl()]. + +list_elements(#c_cons{hd = Head, tl = Tail}) -> + [Head | list_elements(Tail)]; +list_elements(#c_literal{val = V}) -> + abstract_list(V). + +abstract_list([X | Xs]) -> + [abstract(X) | abstract_list(Xs)]; +abstract_list([]) -> + []. + + +%% @spec list_length(Node::cerl()) -> integer() +%% +%% @doc Returns the number of element subtrees of an abstract list. +%% Node must represent a proper list. E.g., if +%% Node represents "[X1 | [X2, X3 | [X4, X5, +%% X6]]]", then list_length(Node) returns the +%% integer 6. +%% +%%

Note: this is equivalent to +%% length(list_elements(Node)), but potentially more +%% efficient.

+%% +%% @see c_cons/2 +%% @see c_nil/1 +%% @see is_c_list/1 +%% @see list_elements/1 + +-spec list_length(c_cons() | c_literal()) -> non_neg_integer(). + +list_length(L) -> + list_length(L, 0). + +list_length(#c_cons{tl = Tail}, A) -> + list_length(Tail, A + 1); +list_length(#c_literal{val = V}, A) -> + A + length(V). + + +%% @spec make_list(List) -> Node +%% @equiv make_list(List, none) + +-spec make_list([cerl()]) -> cerl(). + +make_list(List) -> + ann_make_list([], List). + + +%% @spec make_list(List::[cerl()], Tail) -> cerl() +%% +%% Tail = cerl() | none +%% +%% @doc Creates an abstract list from the elements in List +%% and the optional Tail. If Tail is +%% none, the result will represent a nil-terminated list, +%% otherwise it represents "[... | Tail]". +%% +%% @see c_cons/2 +%% @see c_nil/0 +%% @see ann_make_list/3 +%% @see update_list/3 +%% @see list_elements/1 + +-spec make_list([cerl()], cerl() | 'none') -> cerl(). + +make_list(List, Tail) -> + ann_make_list([], List, Tail). + + +%% @spec update_list(Old::cerl(), List::[cerl()]) -> cerl() +%% @equiv update_list(Old, List, none) + +-spec update_list(cerl(), [cerl()]) -> cerl(). + +update_list(Node, List) -> + ann_make_list(get_ann(Node), List). + + +%% @spec update_list(Old::cerl(), List::[cerl()], Tail) -> cerl() +%% +%% Tail = cerl() | none +%% +%% @see make_list/2 +%% @see update_list/2 + +-spec update_list(cerl(), [cerl()], cerl() | 'none') -> cerl(). + +update_list(Node, List, Tail) -> + ann_make_list(get_ann(Node), List, Tail). + + +%% @spec ann_make_list(As::[term()], List::[cerl()]) -> cerl() +%% @equiv ann_make_list(As, List, none) + +-spec ann_make_list([term()], [cerl()]) -> cerl(). + +ann_make_list(As, List) -> + ann_make_list(As, List, none). + + +%% @spec ann_make_list(As::[term()], List::[cerl()], Tail) -> cerl() +%% +%% Tail = cerl() | none +%% +%% @see make_list/2 +%% @see ann_make_list/2 + +-spec ann_make_list([term()], [cerl()], cerl() | 'none') -> cerl(). + +ann_make_list(As, [H | T], Tail) -> + ann_c_cons(As, H, make_list(T, Tail)); % `c_cons' folds literals +ann_make_list(As, [], none) -> + ann_c_nil(As); +ann_make_list(_, [], Node) -> + Node. + + +%% --------------------------------------------------------------------- + +%% @spec c_tuple(Elements::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract tuple. If Elements is +%% [E1, ..., En], the result represents +%% "{E1, ..., En}". Note that if all +%% nodes in Elements have type literal, or if +%% Elements is empty, then the result will also have type +%% literal and annotations on nodes in +%% Elements are lost. +%% +%%

Recall that Erlang has distinct 1-tuples, i.e., {X} +%% is always distinct from X itself.

+%% +%% @see ann_c_tuple/2 +%% @see update_c_tuple/2 +%% @see is_c_tuple/1 +%% @see tuple_es/1 +%% @see tuple_arity/1 +%% @see c_tuple_skel/1 + +%% *Always* collapse literals. + +-spec c_tuple([cerl()]) -> c_tuple() | c_literal(). + +c_tuple(Es) -> + case is_lit_list(Es) of + false -> + #c_tuple{es = Es}; + true -> + #c_literal{val = list_to_tuple(lit_list_vals(Es))} + end. + + +%% @spec ann_c_tuple(As::[term()], Elements::[cerl()]) -> cerl() +%% @see c_tuple/1 + +-spec ann_c_tuple([term()], [cerl()]) -> c_tuple() | c_literal(). + +ann_c_tuple(As, Es) -> + case is_lit_list(Es) of + false -> + #c_tuple{es = Es, anno = As}; + true -> + #c_literal{val = list_to_tuple(lit_list_vals(Es)), anno = As} + end. + + +%% @spec update_c_tuple(Old::cerl(), Elements::[cerl()]) -> cerl() +%% @see c_tuple/1 + +-spec update_c_tuple(c_tuple() | c_literal(), [cerl()]) -> c_tuple() | c_literal(). + +update_c_tuple(Node, Es) -> + case is_lit_list(Es) of + false -> + #c_tuple{es = Es, anno = get_ann(Node)}; + true -> + #c_literal{val = list_to_tuple(lit_list_vals(Es)), + anno = get_ann(Node)} + end. + + +%% @spec c_tuple_skel(Elements::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract tuple skeleton. Does not fold constant +%% literals, i.e., the result always has type tuple, +%% representing "{E1, ..., En}", if +%% Elements is [E1, ..., En]. +%% +%%

This function is occasionally useful when it is necessary to have +%% annotations on the subnodes of a tuple node, even when all the +%% subnodes are constant literals. Note however that +%% is_literal/1 will yield false and +%% concrete/1 will fail if passed the result from this +%% function.

+%% +%%

fold_literal/1 can be used to revert a node to the +%% normal-form representation.

+%% +%% @see ann_c_tuple_skel/2 +%% @see update_c_tuple_skel/2 +%% @see c_tuple/1 +%% @see tuple_es/1 +%% @see is_c_tuple/1 +%% @see is_literal/1 +%% @see fold_literal/1 +%% @see concrete/1 + +%% *Never* collapse literals. + +-spec c_tuple_skel([cerl()]) -> c_tuple(). + +c_tuple_skel(Es) -> + #c_tuple{es = Es}. + + +%% @spec ann_c_tuple_skel(As::[term()], Elements::[cerl()]) -> cerl() +%% @see c_tuple_skel/1 + +-spec ann_c_tuple_skel([term()], [cerl()]) -> c_tuple(). + +ann_c_tuple_skel(As, Es) -> + #c_tuple{es = Es, anno = As}. + + +%% @spec update_c_tuple_skel(Old::cerl(), Elements::[cerl()]) -> cerl() +%% @see c_tuple_skel/1 + +-spec update_c_tuple_skel(c_tuple(), [cerl()]) -> c_tuple(). + +update_c_tuple_skel(Old, Es) -> + #c_tuple{es = Es, anno = get_ann(Old)}. + + +%% @spec is_c_tuple(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% tuple, otherwise false. +%% +%% @see c_tuple/1 + +-spec is_c_tuple(cerl()) -> boolean(). + +is_c_tuple(#c_tuple{}) -> + true; +is_c_tuple(#c_literal{val = V}) when is_tuple(V) -> + true; +is_c_tuple(_) -> + false. + + +%% @spec tuple_es(cerl()) -> [cerl()] +%% +%% @doc Returns the list of element subtrees of an abstract tuple. +%% +%% @see c_tuple/1 + +-spec tuple_es(c_tuple() | c_literal()) -> [cerl()]. + +tuple_es(#c_tuple{es = Es}) -> + Es; +tuple_es(#c_literal{val = V}) -> + make_lit_list(tuple_to_list(V)). + + +%% @spec tuple_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of element subtrees of an abstract tuple. +%% +%%

Note: this is equivalent to length(tuple_es(Node)), +%% but potentially more efficient.

+%% +%% @see tuple_es/1 +%% @see c_tuple/1 + +-spec tuple_arity(c_tuple() | c_literal()) -> non_neg_integer(). + +tuple_arity(#c_tuple{es = Es}) -> + length(Es); +tuple_arity(#c_literal{val = V}) when is_tuple(V) -> + tuple_size(V). + + +%% --------------------------------------------------------------------- + +%% @spec c_var(Name::var_name()) -> cerl() +%% +%% var_name() = integer() | atom() | {atom(), integer()} +%% +%% @doc Creates an abstract variable. A variable is identified by its +%% name, given by the Name parameter. +%% +%%

If a name is given by a single atom, it should either be a +%% "simple" atom which does not need to be single-quoted in Erlang, or +%% otherwise its print name should correspond to a proper Erlang +%% variable, i.e., begin with an uppercase character or an +%% underscore. Names on the form {A, N} represent +%% function name variables "A/N"; these +%% are special variables which may be bound only in the function +%% definitions of a module or a letrec. They may not be +%% bound in let expressions and cannot occur in clause +%% patterns. The atom A in a function name may be any +%% atom; the integer N must be nonnegative. The functions +%% c_fname/2 etc. are utilities for handling function +%% name variables.

+%% +%%

When printing variable names, they must have the form of proper +%% Core Erlang variables and function names. E.g., a name represented +%% by an integer such as 42 could be formatted as +%% "_42", an atom 'Xxx' simply as +%% "Xxx", and an atom foo as +%% "_foo". However, one must assure that any two valid +%% distinct names are never mapped to the same strings. Tuples such +%% as {foo, 2} representing function names can simply by +%% formatted as "'foo'/2", with no risk of conflicts.

+%% +%% @see ann_c_var/2 +%% @see update_c_var/2 +%% @see is_c_var/1 +%% @see var_name/1 +%% @see c_fname/2 +%% @see c_module/4 +%% @see c_letrec/2 + +-spec c_var(var_name()) -> c_var(). + +c_var(Name) -> + #c_var{name = Name}. + + +%% @spec ann_c_var(As::[term()], Name::var_name()) -> cerl() +%% +%% @see c_var/1 + +-spec ann_c_var([term()], var_name()) -> c_var(). + +ann_c_var(As, Name) -> + #c_var{name = Name, anno = As}. + +%% @spec update_c_var(Old::cerl(), Name::var_name()) -> cerl() +%% +%% @see c_var/1 + +-spec update_c_var(c_var(), var_name()) -> c_var(). + +update_c_var(Node, Name) -> + #c_var{name = Name, anno = get_ann(Node)}. + + +%% @spec is_c_var(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% variable, otherwise false. +%% +%% @see c_var/1 + +-spec is_c_var(cerl()) -> boolean(). + +is_c_var(#c_var{}) -> + true; +is_c_var(_) -> + false. + + +%% @spec c_fname(Name::atom(), Arity::integer()) -> cerl() +%% @equiv c_var({Name, Arity}) +%% @see fname_id/1 +%% @see fname_arity/1 +%% @see is_c_fname/1 +%% @see ann_c_fname/3 +%% @see update_c_fname/3 + +-spec c_fname(atom(), non_neg_integer()) -> c_var(). + +c_fname(Atom, Arity) -> + c_var({Atom, Arity}). + + +%% @spec ann_c_fname(As::[term()], Name::atom(), Arity::integer()) -> +%% cerl() +%% @equiv ann_c_var(As, {Atom, Arity}) +%% @see c_fname/2 + +-spec ann_c_fname([term()], atom(), non_neg_integer()) -> c_var(). + +ann_c_fname(As, Atom, Arity) -> + ann_c_var(As, {Atom, Arity}). + + +%% @spec update_c_fname(Old::cerl(), Name::atom()) -> cerl() +%% @doc Like update_c_fname/3, but takes the arity from +%% Node. +%% @see update_c_fname/3 +%% @see c_fname/2 + +-spec update_c_fname(c_var(), atom()) -> c_var(). + +update_c_fname(#c_var{name = {_, Arity}, anno = As}, Atom) -> + #c_var{name = {Atom, Arity}, anno = As}. + + +%% @spec update_c_fname(Old::cerl(), Name::atom(), Arity::integer()) -> +%% cerl() +%% @equiv update_c_var(Old, {Atom, Arity}) +%% @see update_c_fname/2 +%% @see c_fname/2 + +-spec update_c_fname(c_var(), atom(), integer()) -> c_var(). + +update_c_fname(Node, Atom, Arity) -> + update_c_var(Node, {Atom, Arity}). + + +%% @spec is_c_fname(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% function name variable, otherwise false. +%% +%% @see c_fname/2 +%% @see c_var/1 +%% @see c_var_name/1 + +-spec is_c_fname(cerl()) -> boolean(). + +is_c_fname(#c_var{name = {A, N}}) when is_atom(A), is_integer(N), N >= 0 -> + true; +is_c_fname(_) -> + false. + + +%% @spec var_name(cerl()) -> var_name() +%% +%% @doc Returns the name of an abstract variable. +%% +%% @see c_var/1 + +-spec var_name(c_var()) -> var_name(). + +var_name(Node) -> + Node#c_var.name. + + +%% @spec fname_id(cerl()) -> atom() +%% +%% @doc Returns the identifier part of an abstract function name +%% variable. +%% +%% @see fname_arity/1 +%% @see c_fname/2 + +-spec fname_id(c_var()) -> atom(). + +fname_id(#c_var{name={A,_}}) -> + A. + + +%% @spec fname_arity(cerl()) -> byte() +%% +%% @doc Returns the arity part of an abstract function name variable. +%% +%% @see fname_id/1 +%% @see c_fname/2 + +-spec fname_arity(c_var()) -> byte(). + +fname_arity(#c_var{name={_,N}}) -> + N. + + +%% --------------------------------------------------------------------- + +%% @spec c_values(Elements::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract value list. If Elements is +%% [E1, ..., En], the result represents +%% "<E1, ..., En>". +%% +%% @see ann_c_values/2 +%% @see update_c_values/2 +%% @see is_c_values/1 +%% @see values_es/1 +%% @see values_arity/1 + +-spec c_values([cerl()]) -> c_values(). + +c_values(Es) -> + #c_values{es = Es}. + + +%% @spec ann_c_values(As::[term()], Elements::[cerl()]) -> cerl() +%% @see c_values/1 + +-spec ann_c_values([term()], [cerl()]) -> c_values(). + +ann_c_values(As, Es) -> + #c_values{es = Es, anno = As}. + + +%% @spec update_c_values(Old::cerl(), Elements::[cerl()]) -> cerl() +%% @see c_values/1 + +-spec update_c_values(c_values(), [cerl()]) -> c_values(). + +update_c_values(Node, Es) -> + #c_values{es = Es, anno = get_ann(Node)}. + + +%% @spec is_c_values(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% value list; otherwise false. +%% +%% @see c_values/1 + +-spec is_c_values(cerl()) -> boolean(). + +is_c_values(#c_values{}) -> + true; +is_c_values(_) -> + false. + + +%% @spec values_es(cerl()) -> [cerl()] +%% +%% @doc Returns the list of element subtrees of an abstract value +%% list. +%% +%% @see c_values/1 +%% @see values_arity/1 + +-spec values_es(c_values()) -> [cerl()]. + +values_es(Node) -> + Node#c_values.es. + + +%% @spec values_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of element subtrees of an abstract value +%% list. +%% +%%

Note: This is equivalent to +%% length(values_es(Node)), but potentially more +%% efficient.

+%% +%% @see c_values/1 +%% @see values_es/1 + +-spec values_arity(c_values()) -> non_neg_integer(). + +values_arity(Node) -> + length(values_es(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_binary(Segments::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract binary-template. A binary object is a +%% sequence of 8-bit bytes. It is specified by zero or more bit-string +%% template segments of arbitrary lengths (in number of bits), +%% such that the sum of the lengths is evenly divisible by 8. If +%% Segments is [S1, ..., Sn], the result +%% represents "#{S1, ..., Sn}#". All the +%% Si must have type bitstr. +%% +%% @see ann_c_binary/2 +%% @see update_c_binary/2 +%% @see is_c_binary/1 +%% @see binary_segments/1 +%% @see c_bitstr/5 + +-spec c_binary([cerl()]) -> c_binary(). + +c_binary(Segments) -> + #c_binary{segments = Segments}. + + +%% @spec ann_c_binary(As::[term()], Segments::[cerl()]) -> cerl() +%% @see c_binary/1 + +-spec ann_c_binary([term()], [cerl()]) -> c_binary(). + +ann_c_binary(As, Segments) -> + #c_binary{segments = Segments, anno = As}. + + +%% @spec update_c_binary(Old::cerl(), Segments::[cerl()]) -> cerl() +%% @see c_binary/1 + +-spec update_c_binary(c_binary(), [cerl()]) -> c_binary(). + +update_c_binary(Node, Segments) -> + #c_binary{segments = Segments, anno = get_ann(Node)}. + + +%% @spec is_c_binary(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% binary-template; otherwise false. +%% +%% @see c_binary/1 + +-spec is_c_binary(cerl()) -> boolean(). + +is_c_binary(#c_binary{}) -> + true; +is_c_binary(_) -> + false. + + +%% @spec binary_segments(cerl()) -> [cerl()] +%% +%% @doc Returns the list of segment subtrees of an abstract +%% binary-template. +%% +%% @see c_binary/1 +%% @see c_bitstr/5 + +-spec binary_segments(c_binary()) -> [cerl()]. + +binary_segments(Node) -> + Node#c_binary.segments. + + +%% @spec c_bitstr(Value::cerl(), Size::cerl(), Unit::cerl(), +%% Type::cerl(), Flags::cerl()) -> cerl() +%% +%% @doc Creates an abstract bit-string template. These can only occur as +%% components of an abstract binary-template (see {@link c_binary/1}). +%% The result represents "#<Value>(Size, +%% Unit, Type, Flags)", where +%% Unit must represent a positive integer constant, +%% Type must represent a constant atom (one of +%% 'integer', 'float', or +%% 'binary'), and Flags must represent a +%% constant list "[F1, ..., Fn]" where +%% all the Fi are atoms. +%% +%% @see c_binary/1 +%% @see ann_c_bitstr/6 +%% @see update_c_bitstr/6 +%% @see is_c_bitstr/1 +%% @see bitstr_val/1 +%% @see bitstr_size/1 +%% @see bitstr_unit/1 +%% @see bitstr_type/1 +%% @see bitstr_flags/1 + +-spec c_bitstr(cerl(), cerl(), cerl(), cerl(), cerl()) -> c_bitstr(). + +c_bitstr(Val, Size, Unit, Type, Flags) -> + #c_bitstr{val = Val, size = Size, unit = Unit, type = Type, + flags = Flags}. + + +%% @spec c_bitstr(Value::cerl(), Size::cerl(), Type::cerl(), +%% Flags::cerl()) -> cerl() +%% @equiv c_bitstr(Value, Size, abstract(1), Type, Flags) + +-spec c_bitstr(cerl(), cerl(), cerl(), cerl()) -> c_bitstr(). + +c_bitstr(Val, Size, Type, Flags) -> + c_bitstr(Val, Size, abstract(1), Type, Flags). + + +%% @spec c_bitstr(Value::cerl(), Type::cerl(), +%% Flags::cerl()) -> cerl() +%% @equiv c_bitstr(Value, abstract(all), abstract(1), Type, Flags) + +-spec c_bitstr(cerl(), cerl(), cerl()) -> c_bitstr(). + +c_bitstr(Val, Type, Flags) -> + c_bitstr(Val, abstract(all), abstract(1), Type, Flags). + + +%% @spec ann_c_bitstr(As::[term()], Value::cerl(), Size::cerl(), +%% Unit::cerl(), Type::cerl(), Flags::cerl()) -> cerl() +%% @see c_bitstr/5 +%% @see ann_c_bitstr/5 + +-spec ann_c_bitstr([term()], cerl(), cerl(), cerl(), cerl(), cerl()) -> + c_bitstr(). + +ann_c_bitstr(As, Val, Size, Unit, Type, Flags) -> + #c_bitstr{val = Val, size = Size, unit = Unit, type = Type, + flags = Flags, anno = As}. + +%% @spec ann_c_bitstr(As::[term()], Value::cerl(), Size::cerl(), +%% Type::cerl(), Flags::cerl()) -> cerl() +%% @equiv ann_c_bitstr(As, Value, Size, abstract(1), Type, Flags) + +-spec ann_c_bitstr([term()], cerl(), cerl(), cerl(), cerl()) -> c_bitstr(). + +ann_c_bitstr(As, Value, Size, Type, Flags) -> + ann_c_bitstr(As, Value, Size, abstract(1), Type, Flags). + + +%% @spec update_c_bitstr(Old::cerl(), Value::cerl(), Size::cerl(), +%% Unit::cerl(), Type::cerl(), Flags::cerl()) -> cerl() +%% @see c_bitstr/5 +%% @see update_c_bitstr/5 + +-spec update_c_bitstr(c_bitstr(), cerl(), cerl(), cerl(), cerl(), cerl()) -> + c_bitstr(). + +update_c_bitstr(Node, Val, Size, Unit, Type, Flags) -> + #c_bitstr{val = Val, size = Size, unit = Unit, type = Type, + flags = Flags, anno = get_ann(Node)}. + + +%% @spec update_c_bitstr(Old::cerl(), Value::cerl(), Size::cerl(), +%% Type::cerl(), Flags::cerl()) -> cerl() +%% @equiv update_c_bitstr(Node, Value, Size, abstract(1), Type, Flags) + +-spec update_c_bitstr(c_bitstr(), cerl(), cerl(), cerl(), cerl()) -> c_bitstr(). + +update_c_bitstr(Node, Value, Size, Type, Flags) -> + update_c_bitstr(Node, Value, Size, abstract(1), Type, Flags). + +%% @spec is_c_bitstr(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% bit-string template; otherwise false. +%% +%% @see c_bitstr/5 + +-spec is_c_bitstr(cerl()) -> boolean(). + +is_c_bitstr(#c_bitstr{}) -> + true; +is_c_bitstr(_) -> + false. + + +%% @spec bitstr_val(cerl()) -> cerl() +%% +%% @doc Returns the value subtree of an abstract bit-string template. +%% +%% @see c_bitstr/5 + +-spec bitstr_val(c_bitstr()) -> cerl(). + +bitstr_val(Node) -> + Node#c_bitstr.val. + + +%% @spec bitstr_size(cerl()) -> cerl() +%% +%% @doc Returns the size subtree of an abstract bit-string template. +%% +%% @see c_bitstr/5 + +-spec bitstr_size(c_bitstr()) -> cerl(). + +bitstr_size(Node) -> + Node#c_bitstr.size. + + +%% @spec bitstr_bitsize(cerl()) -> any | all | utf | integer() +%% +%% @doc Returns the total size in bits of an abstract bit-string +%% template. If the size field is an integer literal, the result is the +%% product of the size and unit values; if the size field is the atom +%% literal all, the atom all is returned. +%% If the size is not a literal, the atom any is returned. +%% +%% @see c_bitstr/5 + +-spec bitstr_bitsize(c_bitstr()) -> 'all' | 'any' | 'utf' | non_neg_integer(). + +bitstr_bitsize(Node) -> + Size = Node#c_bitstr.size, + case is_literal(Size) of + true -> + case concrete(Size) of + all -> + all; + undefined -> + %% just an assertion below + "utf" ++ _ = atom_to_list(concrete(Node#c_bitstr.type)), + utf; + S when is_integer(S) -> + S * concrete(Node#c_bitstr.unit) + end; + false -> + any + end. + + +%% @spec bitstr_unit(cerl()) -> cerl() +%% +%% @doc Returns the unit subtree of an abstract bit-string template. +%% +%% @see c_bitstr/5 + +-spec bitstr_unit(c_bitstr()) -> cerl(). + +bitstr_unit(Node) -> + Node#c_bitstr.unit. + + +%% @spec bitstr_type(cerl()) -> cerl() +%% +%% @doc Returns the type subtree of an abstract bit-string template. +%% +%% @see c_bitstr/5 + +-spec bitstr_type(c_bitstr()) -> cerl(). + +bitstr_type(Node) -> + Node#c_bitstr.type. + + +%% @spec bitstr_flags(cerl()) -> cerl() +%% +%% @doc Returns the flags subtree of an abstract bit-string template. +%% +%% @see c_bitstr/5 + +-spec bitstr_flags(c_bitstr()) -> cerl(). + +bitstr_flags(Node) -> + Node#c_bitstr.flags. + + +%% --------------------------------------------------------------------- + +%% @spec c_fun(Variables::[cerl()], Body::cerl()) -> cerl() +%% +%% @doc Creates an abstract fun-expression. If Variables +%% is [V1, ..., Vn], the result represents "fun +%% (V1, ..., Vn) -> Body". All the +%% Vi must have type var. +%% +%% @see ann_c_fun/3 +%% @see update_c_fun/3 +%% @see is_c_fun/1 +%% @see fun_vars/1 +%% @see fun_body/1 +%% @see fun_arity/1 + +-spec c_fun([cerl()], cerl()) -> c_fun(). + +c_fun(Variables, Body) -> + #c_fun{vars = Variables, body = Body}. + + +%% @spec ann_c_fun(As::[term()], Variables::[cerl()], Body::cerl()) -> +%% cerl() +%% @see c_fun/2 + +-spec ann_c_fun([term()], [cerl()], cerl()) -> c_fun(). + +ann_c_fun(As, Variables, Body) -> + #c_fun{vars = Variables, body = Body, anno = As}. + + +%% @spec update_c_fun(Old::cerl(), Variables::[cerl()], +%% Body::cerl()) -> cerl() +%% @see c_fun/2 + +-spec update_c_fun(c_fun(), [cerl()], cerl()) -> c_fun(). + +update_c_fun(Node, Variables, Body) -> + #c_fun{vars = Variables, body = Body, anno = get_ann(Node)}. + + +%% @spec is_c_fun(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% fun-expression, otherwise false. +%% +%% @see c_fun/2 + +-spec is_c_fun(cerl()) -> boolean(). + +is_c_fun(#c_fun{}) -> + true; % Now this is fun! +is_c_fun(_) -> + false. + + +%% @spec fun_vars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of parameter subtrees of an abstract +%% fun-expression. +%% +%% @see c_fun/2 +%% @see fun_arity/1 + +-spec fun_vars(c_fun()) -> [cerl()]. + +fun_vars(Node) -> + Node#c_fun.vars. + + +%% @spec fun_body(cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract fun-expression. +%% +%% @see c_fun/2 + +-spec fun_body(c_fun()) -> cerl(). + +fun_body(Node) -> + Node#c_fun.body. + + +%% @spec fun_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of parameter subtrees of an abstract +%% fun-expression. +%% +%%

Note: this is equivalent to length(fun_vars(Node)), +%% but potentially more efficient.

+%% +%% @see c_fun/2 +%% @see fun_vars/1 + +-spec fun_arity(c_fun()) -> non_neg_integer(). + +fun_arity(Node) -> + length(fun_vars(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_seq(Argument::cerl(), Body::cerl()) -> cerl() +%% +%% @doc Creates an abstract sequencing expression. The result +%% represents "do Argument Body". +%% +%% @see ann_c_seq/3 +%% @see update_c_seq/3 +%% @see is_c_seq/1 +%% @see seq_arg/1 +%% @see seq_body/1 + +-spec c_seq(cerl(), cerl()) -> c_seq(). + +c_seq(Argument, Body) -> + #c_seq{arg = Argument, body = Body}. + + +%% @spec ann_c_seq(As::[term()], Argument::cerl(), Body::cerl()) -> +%% cerl() +%% @see c_seq/2 + +-spec ann_c_seq([term()], cerl(), cerl()) -> c_seq(). + +ann_c_seq(As, Argument, Body) -> + #c_seq{arg = Argument, body = Body, anno = As}. + + +%% @spec update_c_seq(Old::cerl(), Argument::cerl(), Body::cerl()) -> +%% cerl() +%% @see c_seq/2 + +-spec update_c_seq(c_seq(), cerl(), cerl()) -> c_seq(). + +update_c_seq(Node, Argument, Body) -> + #c_seq{arg = Argument, body = Body, anno = get_ann(Node)}. + + +%% @spec is_c_seq(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% sequencing expression, otherwise false. +%% +%% @see c_seq/2 + +-spec is_c_seq(cerl()) -> boolean(). + +is_c_seq(#c_seq{}) -> + true; +is_c_seq(_) -> + false. + + +%% @spec seq_arg(cerl()) -> cerl() +%% +%% @doc Returns the argument subtree of an abstract sequencing +%% expression. +%% +%% @see c_seq/2 + +-spec seq_arg(c_seq()) -> cerl(). + +seq_arg(Node) -> + Node#c_seq.arg. + + +%% @spec seq_body(cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract sequencing expression. +%% +%% @see c_seq/2 + +-spec seq_body(c_seq()) -> cerl(). + +seq_body(Node) -> + Node#c_seq.body. + + +%% --------------------------------------------------------------------- + +%% @spec c_let(Variables::[cerl()], Argument::cerl(), Body::cerl()) -> +%% cerl() +%% +%% @doc Creates an abstract let-expression. If Variables +%% is [V1, ..., Vn], the result represents "let +%% <V1, ..., Vn> = Argument in +%% Body". All the Vi must have type +%% var. +%% +%% @see ann_c_let/4 +%% @see update_c_let/4 +%% @see is_c_let/1 +%% @see let_vars/1 +%% @see let_arg/1 +%% @see let_body/1 +%% @see let_arity/1 + +-spec c_let([cerl()], cerl(), cerl()) -> c_let(). + +c_let(Variables, Argument, Body) -> + #c_let{vars = Variables, arg = Argument, body = Body}. + + +%% ann_c_let(As, Variables, Argument, Body) -> Node +%% @see c_let/3 + +-spec ann_c_let([term()], [cerl()], cerl(), cerl()) -> c_let(). + +ann_c_let(As, Variables, Argument, Body) -> + #c_let{vars = Variables, arg = Argument, body = Body, anno = As}. + + +%% update_c_let(Old, Variables, Argument, Body) -> Node +%% @see c_let/3 + +-spec update_c_let(c_let(), [cerl()], cerl(), cerl()) -> c_let(). + +update_c_let(Node, Variables, Argument, Body) -> + #c_let{vars = Variables, arg = Argument, body = Body, + anno = get_ann(Node)}. + + +%% @spec is_c_let(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% let-expression, otherwise false. +%% +%% @see c_let/3 + +-spec is_c_let(cerl()) -> boolean(). + +is_c_let(#c_let{}) -> + true; +is_c_let(_) -> + false. + + +%% @spec let_vars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of left-hand side variables of an abstract +%% let-expression. +%% +%% @see c_let/3 +%% @see let_arity/1 + +-spec let_vars(c_let()) -> [cerl()]. + +let_vars(Node) -> + Node#c_let.vars. + + +%% @spec let_arg(cerl()) -> cerl() +%% +%% @doc Returns the argument subtree of an abstract let-expression. +%% +%% @see c_let/3 + +-spec let_arg(c_let()) -> cerl(). + +let_arg(Node) -> + Node#c_let.arg. + + +%% @spec let_body(cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract let-expression. +%% +%% @see c_let/3 + +-spec let_body(c_let()) -> cerl(). + +let_body(Node) -> + Node#c_let.body. + + +%% @spec let_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of left-hand side variables of an abstract +%% let-expression. +%% +%%

Note: this is equivalent to length(let_vars(Node)), +%% but potentially more efficient.

+%% +%% @see c_let/3 +%% @see let_vars/1 + +-spec let_arity(c_let()) -> non_neg_integer(). + +let_arity(Node) -> + length(let_vars(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_letrec(Definitions::[{cerl(), cerl()}], Body::cerl()) -> +%% cerl() +%% +%% @doc Creates an abstract letrec-expression. If +%% Definitions is [{V1, F1}, ..., {Vn, Fn}], +%% the result represents "letrec V1 = F1 +%% ... Vn = Fn in Body. All the +%% Vi must have type var and represent +%% function names. All the Fi must have type +%% 'fun'. +%% +%% @see ann_c_letrec/3 +%% @see update_c_letrec/3 +%% @see is_c_letrec/1 +%% @see letrec_defs/1 +%% @see letrec_body/1 +%% @see letrec_vars/1 + +-spec c_letrec([{cerl(), cerl()}], cerl()) -> c_letrec(). + +c_letrec(Defs, Body) -> + #c_letrec{defs = Defs, body = Body}. + + +%% @spec ann_c_letrec(As::[term()], Definitions::[{cerl(), cerl()}], +%% Body::cerl()) -> cerl() +%% @see c_letrec/2 + +-spec ann_c_letrec([term()], [{cerl(), cerl()}], cerl()) -> c_letrec(). + +ann_c_letrec(As, Defs, Body) -> + #c_letrec{defs = Defs, body = Body, anno = As}. + + +%% @spec update_c_letrec(Old::cerl(), +%% Definitions::[{cerl(), cerl()}], +%% Body::cerl()) -> cerl() +%% @see c_letrec/2 + +-spec update_c_letrec(c_letrec(), [{cerl(), cerl()}], cerl()) -> c_letrec(). + +update_c_letrec(Node, Defs, Body) -> + #c_letrec{defs = Defs, body = Body, anno = get_ann(Node)}. + + +%% @spec is_c_letrec(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% letrec-expression, otherwise false. +%% +%% @see c_letrec/2 + +-spec is_c_letrec(cerl()) -> boolean(). + +is_c_letrec(#c_letrec{}) -> + true; +is_c_letrec(_) -> + false. + + +%% @spec letrec_defs(Node::cerl()) -> [{cerl(), cerl()}] +%% +%% @doc Returns the list of definitions of an abstract +%% letrec-expression. If Node represents "letrec +%% V1 = F1 ... Vn = Fn in +%% Body", the returned value is [{V1, F1}, ..., +%% {Vn, Fn}]. +%% +%% @see c_letrec/2 + +-spec letrec_defs(c_letrec()) -> [{cerl(), cerl()}]. + +letrec_defs(Node) -> + Node#c_letrec.defs. + + +%% @spec letrec_body(cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract letrec-expression. +%% +%% @see c_letrec/2 + +-spec letrec_body(c_letrec()) -> cerl(). + +letrec_body(Node) -> + Node#c_letrec.body. + + +%% @spec letrec_vars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of left-hand side function variable subtrees +%% of a letrec-expression. If Node represents +%% "letrec V1 = F1 ... Vn = +%% Fn in Body", the returned value is +%% [V1, ..., Vn]. +%% +%% @see c_letrec/2 + +-spec letrec_vars(c_letrec()) -> [cerl()]. + +letrec_vars(Node) -> + [F || {F, _} <- letrec_defs(Node)]. + + +%% --------------------------------------------------------------------- + +%% @spec c_case(Argument::cerl(), Clauses::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract case-expression. If Clauses +%% is [C1, ..., Cn], the result represents "case +%% Argument of C1 ... Cn +%% end". Clauses must not be empty. +%% +%% @see ann_c_case/3 +%% @see update_c_case/3 +%% @see is_c_case/1 +%% @see c_clause/3 +%% @see case_arg/1 +%% @see case_clauses/1 +%% @see case_arity/1 + +-spec c_case(cerl(), [cerl()]) -> c_case(). + +c_case(Expr, Clauses) -> + #c_case{arg = Expr, clauses = Clauses}. + + +%% @spec ann_c_case(As::[term()], Argument::cerl(), +%% Clauses::[cerl()]) -> cerl() +%% @see c_case/2 + +-spec ann_c_case([term()], cerl(), [cerl()]) -> c_case(). + +ann_c_case(As, Expr, Clauses) -> + #c_case{arg = Expr, clauses = Clauses, anno = As}. + + +%% @spec update_c_case(Old::cerl(), Argument::cerl(), +%% Clauses::[cerl()]) -> cerl() +%% @see c_case/2 + +-spec update_c_case(c_case(), cerl(), [cerl()]) -> c_case(). + +update_c_case(Node, Expr, Clauses) -> + #c_case{arg = Expr, clauses = Clauses, anno = get_ann(Node)}. + + +%% is_c_case(Node) -> boolean() +%% +%% Node = cerl() +%% +%% @doc Returns true if Node is an abstract +%% case-expression; otherwise false. +%% +%% @see c_case/2 + +-spec is_c_case(cerl()) -> boolean(). + +is_c_case(#c_case{}) -> + true; +is_c_case(_) -> + false. + + +%% @spec case_arg(cerl()) -> cerl() +%% +%% @doc Returns the argument subtree of an abstract case-expression. +%% +%% @see c_case/2 + +-spec case_arg(c_case()) -> cerl(). + +case_arg(Node) -> + Node#c_case.arg. + + +%% @spec case_clauses(cerl()) -> [cerl()] +%% +%% @doc Returns the list of clause subtrees of an abstract +%% case-expression. +%% +%% @see c_case/2 +%% @see case_arity/1 + +-spec case_clauses(c_case()) -> [cerl()]. + +case_clauses(Node) -> + Node#c_case.clauses. + + +%% @spec case_arity(Node::cerl()) -> integer() +%% +%% @doc Equivalent to +%% clause_arity(hd(case_clauses(Node))), but potentially +%% more efficient. +%% +%% @see c_case/2 +%% @see case_clauses/1 +%% @see clause_arity/1 + +-spec case_arity(c_case()) -> non_neg_integer(). + +case_arity(Node) -> + clause_arity(hd(case_clauses(Node))). + + +%% --------------------------------------------------------------------- + +%% @spec c_clause(Patterns::[cerl()], Body::cerl()) -> cerl() +%% @equiv c_clause(Patterns, c_atom(true), Body) +%% @see c_atom/1 + +-spec c_clause([cerl()], cerl()) -> c_clause(). + +c_clause(Patterns, Body) -> + c_clause(Patterns, c_atom(true), Body). + + +%% @spec c_clause(Patterns::[cerl()], Guard::cerl(), Body::cerl()) -> +%% cerl() +%% +%% @doc Creates an an abstract clause. If Patterns is +%% [P1, ..., Pn], the result represents +%% "<P1, ..., Pn> when Guard -> +%% Body". +%% +%% @see c_clause/2 +%% @see ann_c_clause/4 +%% @see update_c_clause/4 +%% @see is_c_clause/1 +%% @see c_case/2 +%% @see c_receive/3 +%% @see clause_pats/1 +%% @see clause_guard/1 +%% @see clause_body/1 +%% @see clause_arity/1 +%% @see clause_vars/1 + +-spec c_clause([cerl()], cerl(), cerl()) -> c_clause(). + +c_clause(Patterns, Guard, Body) -> + #c_clause{pats = Patterns, guard = Guard, body = Body}. + + +%% @spec ann_c_clause(As::[term()], Patterns::[cerl()], +%% Body::cerl()) -> cerl() +%% @equiv ann_c_clause(As, Patterns, c_atom(true), Body) +%% @see c_clause/3 + +-spec ann_c_clause([term()], [cerl()], cerl()) -> c_clause(). + +ann_c_clause(As, Patterns, Body) -> + ann_c_clause(As, Patterns, c_atom(true), Body). + + +%% @spec ann_c_clause(As::[term()], Patterns::[cerl()], Guard::cerl(), +%% Body::cerl()) -> cerl() +%% @see ann_c_clause/3 +%% @see c_clause/3 + +-spec ann_c_clause([term()], [cerl()], cerl(), cerl()) -> c_clause(). + +ann_c_clause(As, Patterns, Guard, Body) -> + #c_clause{pats = Patterns, guard = Guard, body = Body, anno = As}. + + +%% @spec update_c_clause(Old::cerl(), Patterns::[cerl()], +%% Guard::cerl(), Body::cerl()) -> cerl() +%% @see c_clause/3 + +-spec update_c_clause(c_clause(), [cerl()], cerl(), cerl()) -> c_clause(). + +update_c_clause(Node, Patterns, Guard, Body) -> + #c_clause{pats = Patterns, guard = Guard, body = Body, + anno = get_ann(Node)}. + + +%% @spec is_c_clause(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% clause, otherwise false. +%% +%% @see c_clause/3 + +-spec is_c_clause(cerl()) -> boolean(). + +is_c_clause(#c_clause{}) -> + true; +is_c_clause(_) -> + false. + + +%% @spec clause_pats(cerl()) -> [cerl()] +%% +%% @doc Returns the list of pattern subtrees of an abstract clause. +%% +%% @see c_clause/3 +%% @see clause_arity/1 + +-spec clause_pats(c_clause()) -> [cerl()]. + +clause_pats(Node) -> + Node#c_clause.pats. + + +%% @spec clause_guard(cerl()) -> cerl() +%% +%% @doc Returns the guard subtree of an abstract clause. +%% +%% @see c_clause/3 + +-spec clause_guard(c_clause()) -> cerl(). + +clause_guard(Node) -> + Node#c_clause.guard. + + +%% @spec clause_body(cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract clause. +%% +%% @see c_clause/3 + +-spec clause_body(c_clause()) -> cerl(). + +clause_body(Node) -> + Node#c_clause.body. + + +%% @spec clause_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of pattern subtrees of an abstract clause. +%% +%%

Note: this is equivalent to +%% length(clause_pats(Node)), but potentially more +%% efficient.

+%% +%% @see c_clause/3 +%% @see clause_pats/1 + +-spec clause_arity(c_clause()) -> non_neg_integer(). + +clause_arity(Node) -> + length(clause_pats(Node)). + + +%% @spec clause_vars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of all abstract variables in the patterns of +%% an abstract clause. The order of listing is not defined. +%% +%% @see c_clause/3 +%% @see pat_list_vars/1 + +-spec clause_vars(c_clause()) -> [cerl()]. + +clause_vars(Clause) -> + pat_list_vars(clause_pats(Clause)). + + +%% @spec pat_vars(Pattern::cerl()) -> [cerl()] +%% +%% @doc Returns the list of all abstract variables in a pattern. An +%% exception is thrown if Node does not represent a +%% well-formed Core Erlang clause pattern. The order of listing is not +%% defined. +%% +%% @see pat_list_vars/1 +%% @see clause_vars/1 + +-spec pat_vars(cerl()) -> [cerl()]. + +pat_vars(Node) -> + pat_vars(Node, []). + +pat_vars(Node, Vs) -> + case type(Node) of + var -> + [Node | Vs]; + literal -> + Vs; + cons -> + pat_vars(cons_hd(Node), pat_vars(cons_tl(Node), Vs)); + tuple -> + pat_list_vars(tuple_es(Node), Vs); + binary -> + pat_list_vars(binary_segments(Node), Vs); + bitstr -> + pat_vars(bitstr_val(Node), Vs); + alias -> + pat_vars(alias_pat(Node), [alias_var(Node) | Vs]) + end. + + +%% @spec pat_list_vars(Patterns::[cerl()]) -> [cerl()] +%% +%% @doc Returns the list of all abstract variables in the given +%% patterns. An exception is thrown if some element in +%% Patterns does not represent a well-formed Core Erlang +%% clause pattern. The order of listing is not defined. +%% +%% @see pat_vars/1 +%% @see clause_vars/1 + +-spec pat_list_vars([cerl()]) -> [cerl()]. + +pat_list_vars(Ps) -> + pat_list_vars(Ps, []). + +pat_list_vars([P | Ps], Vs) -> + pat_list_vars(Ps, pat_vars(P, Vs)); +pat_list_vars([], Vs) -> + Vs. + + +%% --------------------------------------------------------------------- + +%% @spec c_alias(Variable::cerl(), Pattern::cerl()) -> cerl() +%% +%% @doc Creates an abstract pattern alias. The result represents +%% "Variable = Pattern". +%% +%% @see ann_c_alias/3 +%% @see update_c_alias/3 +%% @see is_c_alias/1 +%% @see alias_var/1 +%% @see alias_pat/1 +%% @see c_clause/3 + +-spec c_alias(c_var(), cerl()) -> c_alias(). + +c_alias(Var, Pattern) -> + #c_alias{var = Var, pat = Pattern}. + + +%% @spec ann_c_alias(As::[term()], Variable::cerl(), +%% Pattern::cerl()) -> cerl() +%% @see c_alias/2 + +-spec ann_c_alias([term()], c_var(), cerl()) -> c_alias(). + +ann_c_alias(As, Var, Pattern) -> + #c_alias{var = Var, pat = Pattern, anno = As}. + + +%% @spec update_c_alias(Old::cerl(), Variable::cerl(), +%% Pattern::cerl()) -> cerl() +%% @see c_alias/2 + +-spec update_c_alias(c_alias(), cerl(), cerl()) -> c_alias(). + +update_c_alias(Node, Var, Pattern) -> + #c_alias{var = Var, pat = Pattern, anno = get_ann(Node)}. + + +%% @spec is_c_alias(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% pattern alias, otherwise false. +%% +%% @see c_alias/2 + +-spec is_c_alias(cerl()) -> boolean(). + +is_c_alias(#c_alias{}) -> + true; +is_c_alias(_) -> + false. + + +%% @spec alias_var(cerl()) -> cerl() +%% +%% @doc Returns the variable subtree of an abstract pattern alias. +%% +%% @see c_alias/2 + +-spec alias_var(c_alias()) -> c_var(). + +alias_var(Node) -> + Node#c_alias.var. + + +%% @spec alias_pat(cerl()) -> cerl() +%% +%% @doc Returns the pattern subtree of an abstract pattern alias. +%% +%% @see c_alias/2 + +-spec alias_pat(c_alias()) -> cerl(). + +alias_pat(Node) -> + Node#c_alias.pat. + + +%% --------------------------------------------------------------------- + +%% @spec c_receive(Clauses::[cerl()]) -> cerl() +%% @equiv c_receive(Clauses, c_atom(infinity), c_atom(true)) +%% @see c_atom/1 + +-spec c_receive([cerl()]) -> c_receive(). + +c_receive(Clauses) -> + c_receive(Clauses, c_atom(infinity), c_atom(true)). + + +%% @spec c_receive(Clauses::[cerl()], Timeout::cerl(), +%% Action::cerl()) -> cerl() +%% +%% @doc Creates an abstract receive-expression. If +%% Clauses is [C1, ..., Cn], the result +%% represents "receive C1 ... Cn after +%% Timeout -> Action end". +%% +%% @see c_receive/1 +%% @see ann_c_receive/4 +%% @see update_c_receive/4 +%% @see is_c_receive/1 +%% @see receive_clauses/1 +%% @see receive_timeout/1 +%% @see receive_action/1 + +-spec c_receive([cerl()], cerl(), cerl()) -> c_receive(). + +c_receive(Clauses, Timeout, Action) -> + #c_receive{clauses = Clauses, timeout = Timeout, action = Action}. + + +%% @spec ann_c_receive(As::[term()], Clauses::[cerl()]) -> cerl() +%% @equiv ann_c_receive(As, Clauses, c_atom(infinity), c_atom(true)) +%% @see c_receive/3 +%% @see c_atom/1 + +-spec ann_c_receive([term()], [cerl()]) -> c_receive(). + +ann_c_receive(As, Clauses) -> + ann_c_receive(As, Clauses, c_atom(infinity), c_atom(true)). + + +%% @spec ann_c_receive(As::[term()], Clauses::[cerl()], +%% Timeout::cerl(), Action::cerl()) -> cerl() +%% @see ann_c_receive/2 +%% @see c_receive/3 + +-spec ann_c_receive([term()], [cerl()], cerl(), cerl()) -> c_receive(). + +ann_c_receive(As, Clauses, Timeout, Action) -> + #c_receive{clauses = Clauses, timeout = Timeout, action = Action, + anno = As}. + + +%% @spec update_c_receive(Old::cerl(), Clauses::[cerl()], +%% Timeout::cerl(), Action::cerl()) -> cerl() +%% @see c_receive/3 + +-spec update_c_receive(c_receive(), [cerl()], cerl(), cerl()) -> c_receive(). + +update_c_receive(Node, Clauses, Timeout, Action) -> + #c_receive{clauses = Clauses, timeout = Timeout, action = Action, + anno = get_ann(Node)}. + + +%% @spec is_c_receive(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% receive-expression, otherwise false. +%% +%% @see c_receive/3 + +-spec is_c_receive(cerl()) -> boolean(). + +is_c_receive(#c_receive{}) -> + true; +is_c_receive(_) -> + false. + + +%% @spec receive_clauses(cerl()) -> [cerl()] +%% +%% @doc Returns the list of clause subtrees of an abstract +%% receive-expression. +%% +%% @see c_receive/3 + +-spec receive_clauses(c_receive()) -> [cerl()]. + +receive_clauses(Node) -> + Node#c_receive.clauses. + + +%% @spec receive_timeout(cerl()) -> cerl() +%% +%% @doc Returns the timeout subtree of an abstract receive-expression. +%% +%% @see c_receive/3 + +-spec receive_timeout(c_receive()) -> cerl(). + +receive_timeout(Node) -> + Node#c_receive.timeout. + + +%% @spec receive_action(cerl()) -> cerl() +%% +%% @doc Returns the action subtree of an abstract receive-expression. +%% +%% @see c_receive/3 + +-spec receive_action(c_receive()) -> cerl(). + +receive_action(Node) -> + Node#c_receive.action. + + +%% --------------------------------------------------------------------- + +%% @spec c_apply(Operator::cerl(), Arguments::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract function application. If +%% Arguments is [A1, ..., An], the result +%% represents "apply Operator(A1, ..., +%% An)". +%% +%% @see ann_c_apply/3 +%% @see update_c_apply/3 +%% @see is_c_apply/1 +%% @see apply_op/1 +%% @see apply_args/1 +%% @see apply_arity/1 +%% @see c_call/3 +%% @see c_primop/2 + +-spec c_apply(cerl(), [cerl()]) -> c_apply(). + +c_apply(Operator, Arguments) -> + #c_apply{op = Operator, args = Arguments}. + + +%% @spec ann_c_apply(As::[term()], Operator::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_apply/2 + +-spec ann_c_apply([term()], cerl(), [cerl()]) -> c_apply(). + +ann_c_apply(As, Operator, Arguments) -> + #c_apply{op = Operator, args = Arguments, anno = As}. + + +%% @spec update_c_apply(Old::cerl(), Operator::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_apply/2 + +-spec update_c_apply(c_apply(), cerl(), [cerl()]) -> c_apply(). + +update_c_apply(Node, Operator, Arguments) -> + #c_apply{op = Operator, args = Arguments, anno = get_ann(Node)}. + + +%% @spec is_c_apply(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% function application, otherwise false. +%% +%% @see c_apply/2 + +-spec is_c_apply(cerl()) -> boolean(). + +is_c_apply(#c_apply{}) -> + true; +is_c_apply(_) -> + false. + + +%% @spec apply_op(cerl()) -> cerl() +%% +%% @doc Returns the operator subtree of an abstract function +%% application. +%% +%% @see c_apply/2 + +-spec apply_op(c_apply()) -> cerl(). + +apply_op(Node) -> + Node#c_apply.op. + + +%% @spec apply_args(cerl()) -> [cerl()] +%% +%% @doc Returns the list of argument subtrees of an abstract function +%% application. +%% +%% @see c_apply/2 +%% @see apply_arity/1 + +-spec apply_args(c_apply()) -> [cerl()]. + +apply_args(Node) -> + Node#c_apply.args. + + +%% @spec apply_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of argument subtrees of an abstract +%% function application. +%% +%%

Note: this is equivalent to +%% length(apply_args(Node)), but potentially more +%% efficient.

+%% +%% @see c_apply/2 +%% @see apply_args/1 + +-spec apply_arity(c_apply()) -> non_neg_integer(). + +apply_arity(Node) -> + length(apply_args(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_call(Module::cerl(), Name::cerl(), Arguments::[cerl()]) -> +%% cerl() +%% +%% @doc Creates an abstract inter-module call. If +%% Arguments is [A1, ..., An], the result +%% represents "call Module:Name(A1, +%% ..., An)". +%% +%% @see ann_c_call/4 +%% @see update_c_call/4 +%% @see is_c_call/1 +%% @see call_module/1 +%% @see call_name/1 +%% @see call_args/1 +%% @see call_arity/1 +%% @see c_apply/2 +%% @see c_primop/2 + +-spec c_call(cerl(), cerl(), [cerl()]) -> c_call(). + +c_call(Module, Name, Arguments) -> + #c_call{module = Module, name = Name, args = Arguments}. + + +%% @spec ann_c_call(As::[term()], Module::cerl(), Name::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_call/3 + +-spec ann_c_call([term()], cerl(), cerl(), [cerl()]) -> c_call(). + +ann_c_call(As, Module, Name, Arguments) -> + #c_call{module = Module, name = Name, args = Arguments, anno = As}. + + +%% @spec update_c_call(Old::cerl(), Module::cerl(), Name::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_call/3 + +-spec update_c_call(cerl(), cerl(), cerl(), [cerl()]) -> c_call(). + +update_c_call(Node, Module, Name, Arguments) -> + #c_call{module = Module, name = Name, args = Arguments, + anno = get_ann(Node)}. + + +%% @spec is_c_call(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% inter-module call expression; otherwise false. +%% +%% @see c_call/3 + +-spec is_c_call(cerl()) -> boolean(). + +is_c_call(#c_call{}) -> + true; +is_c_call(_) -> + false. + + +%% @spec call_module(cerl()) -> cerl() +%% +%% @doc Returns the module subtree of an abstract inter-module call. +%% +%% @see c_call/3 + +-spec call_module(c_call()) -> cerl(). + +call_module(Node) -> + Node#c_call.module. + + +%% @spec call_name(cerl()) -> cerl() +%% +%% @doc Returns the name subtree of an abstract inter-module call. +%% +%% @see c_call/3 + +-spec call_name(c_call()) -> cerl(). + +call_name(Node) -> + Node#c_call.name. + + +%% @spec call_args(cerl()) -> [cerl()] +%% +%% @doc Returns the list of argument subtrees of an abstract +%% inter-module call. +%% +%% @see c_call/3 +%% @see call_arity/1 + +-spec call_args(c_call()) -> [cerl()]. + +call_args(Node) -> + Node#c_call.args. + + +%% @spec call_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of argument subtrees of an abstract +%% inter-module call. +%% +%%

Note: this is equivalent to +%% length(call_args(Node)), but potentially more +%% efficient.

+%% +%% @see c_call/3 +%% @see call_args/1 + +-spec call_arity(c_call()) -> non_neg_integer(). + +call_arity(Node) -> + length(call_args(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_primop(Name::cerl(), Arguments::[cerl()]) -> cerl() +%% +%% @doc Creates an abstract primitive operation call. If +%% Arguments is [A1, ..., An], the result +%% represents "primop Name(A1, ..., +%% An)". Name must be an atom literal. +%% +%% @see ann_c_primop/3 +%% @see update_c_primop/3 +%% @see is_c_primop/1 +%% @see primop_name/1 +%% @see primop_args/1 +%% @see primop_arity/1 +%% @see c_apply/2 +%% @see c_call/3 + +-spec c_primop(cerl(), [cerl()]) -> c_primop(). + +c_primop(Name, Arguments) -> + #c_primop{name = Name, args = Arguments}. + + +%% @spec ann_c_primop(As::[term()], Name::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_primop/2 + +-spec ann_c_primop([term()], cerl(), [cerl()]) -> c_primop(). + +ann_c_primop(As, Name, Arguments) -> + #c_primop{name = Name, args = Arguments, anno = As}. + + +%% @spec update_c_primop(Old::cerl(), Name::cerl(), +%% Arguments::[cerl()]) -> cerl() +%% @see c_primop/2 + +-spec update_c_primop(cerl(), cerl(), [cerl()]) -> c_primop(). + +update_c_primop(Node, Name, Arguments) -> + #c_primop{name = Name, args = Arguments, anno = get_ann(Node)}. + + +%% @spec is_c_primop(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% primitive operation call, otherwise false. +%% +%% @see c_primop/2 + +-spec is_c_primop(cerl()) -> boolean(). + +is_c_primop(#c_primop{}) -> + true; +is_c_primop(_) -> + false. + + +%% @spec primop_name(cerl()) -> cerl() +%% +%% @doc Returns the name subtree of an abstract primitive operation +%% call. +%% +%% @see c_primop/2 + +-spec primop_name(c_primop()) -> cerl(). + +primop_name(Node) -> + Node#c_primop.name. + + +%% @spec primop_args(cerl()) -> [cerl()] +%% +%% @doc Returns the list of argument subtrees of an abstract primitive +%% operation call. +%% +%% @see c_primop/2 +%% @see primop_arity/1 + +-spec primop_args(c_primop()) -> [cerl()]. + +primop_args(Node) -> + Node#c_primop.args. + + +%% @spec primop_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of argument subtrees of an abstract +%% primitive operation call. +%% +%%

Note: this is equivalent to +%% length(primop_args(Node)), but potentially more +%% efficient.

+%% +%% @see c_primop/2 +%% @see primop_args/1 + +-spec primop_arity(c_primop()) -> non_neg_integer(). + +primop_arity(Node) -> + length(primop_args(Node)). + + +%% --------------------------------------------------------------------- + +%% @spec c_try(Argument::cerl(), Variables::[cerl()], Body::cerl(), +%% ExceptionVars::[cerl()], Handler::cerl()) -> cerl() +%% +%% @doc Creates an abstract try-expression. If Variables is +%% [V1, ..., Vn] and ExceptionVars is +%% [X1, ..., Xm], the result represents "try +%% Argument of <V1, ..., Vn> -> +%% Body catch <X1, ..., Xm> -> +%% Handler". All the Vi and Xi +%% must have type var. +%% +%% @see ann_c_try/6 +%% @see update_c_try/6 +%% @see is_c_try/1 +%% @see try_arg/1 +%% @see try_vars/1 +%% @see try_body/1 +%% @see c_catch/1 + +-spec c_try(cerl(), [cerl()], cerl(), [cerl()], cerl()) -> c_try(). + +c_try(Expr, Vs, Body, Evs, Handler) -> + #c_try{arg = Expr, vars = Vs, body = Body, + evars = Evs, handler = Handler}. + + +%% @spec ann_c_try(As::[term()], Expression::cerl(), +%% Variables::[cerl()], Body::cerl(), +%% EVars::[cerl()], Handler::cerl()) -> cerl() +%% @see c_try/3 + +-spec ann_c_try([term()], cerl(), [cerl()], cerl(), [cerl()], cerl()) -> + c_try(). + +ann_c_try(As, Expr, Vs, Body, Evs, Handler) -> + #c_try{arg = Expr, vars = Vs, body = Body, + evars = Evs, handler = Handler, anno = As}. + + +%% @spec update_c_try(Old::cerl(), Expression::cerl(), +%% Variables::[cerl()], Body::cerl(), +%% EVars::[cerl()], Handler::cerl()) -> cerl() +%% @see c_try/3 + +-spec update_c_try(c_try(), cerl(), [cerl()], cerl(), [cerl()], cerl()) -> + c_try(). + +update_c_try(Node, Expr, Vs, Body, Evs, Handler) -> + #c_try{arg = Expr, vars = Vs, body = Body, + evars = Evs, handler = Handler, anno = get_ann(Node)}. + + +%% @spec is_c_try(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% try-expression, otherwise false. +%% +%% @see c_try/3 + +-spec is_c_try(cerl()) -> boolean(). + +is_c_try(#c_try{}) -> + true; +is_c_try(_) -> + false. + + +%% @spec try_arg(cerl()) -> cerl() +%% +%% @doc Returns the expression subtree of an abstract try-expression. +%% +%% @see c_try/3 + +-spec try_arg(c_try()) -> cerl(). + +try_arg(Node) -> + Node#c_try.arg. + + +%% @spec try_vars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of success variable subtrees of an abstract +%% try-expression. +%% +%% @see c_try/3 + +-spec try_vars(c_try()) -> [cerl()]. + +try_vars(Node) -> + Node#c_try.vars. + + +%% @spec try_body(cerl()) -> cerl() +%% +%% @doc Returns the success body subtree of an abstract try-expression. +%% +%% @see c_try/3 + +-spec try_body(c_try()) -> cerl(). + +try_body(Node) -> + Node#c_try.body. + + +%% @spec try_evars(cerl()) -> [cerl()] +%% +%% @doc Returns the list of exception variable subtrees of an abstract +%% try-expression. +%% +%% @see c_try/3 + +-spec try_evars(c_try()) -> [cerl()]. + +try_evars(Node) -> + Node#c_try.evars. + + +%% @spec try_handler(cerl()) -> cerl() +%% +%% @doc Returns the exception body subtree of an abstract +%% try-expression. +%% +%% @see c_try/3 + +-spec try_handler(c_try()) -> cerl(). + +try_handler(Node) -> + Node#c_try.handler. + + +%% --------------------------------------------------------------------- + +%% @spec c_catch(Body::cerl()) -> cerl() +%% +%% @doc Creates an abstract catch-expression. The result represents +%% "catch Body". +%% +%%

Note: catch-expressions can be rewritten as try-expressions, and +%% will eventually be removed from Core Erlang.

+%% +%% @see ann_c_catch/2 +%% @see update_c_catch/2 +%% @see is_c_catch/1 +%% @see catch_body/1 +%% @see c_try/3 + +-spec c_catch(cerl()) -> c_catch(). + +c_catch(Body) -> + #c_catch{body = Body}. + + +%% @spec ann_c_catch(As::[term()], Body::cerl()) -> cerl() +%% @see c_catch/1 + +-spec ann_c_catch([term()], cerl()) -> c_catch(). + +ann_c_catch(As, Body) -> + #c_catch{body = Body, anno = As}. + + +%% @spec update_c_catch(Old::cerl(), Body::cerl()) -> cerl() +%% @see c_catch/1 + +-spec update_c_catch(c_catch(), cerl()) -> c_catch(). + +update_c_catch(Node, Body) -> + #c_catch{body = Body, anno = get_ann(Node)}. + + +%% @spec is_c_catch(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node is an abstract +%% catch-expression, otherwise false. +%% +%% @see c_catch/1 + +-spec is_c_catch(cerl()) -> boolean(). + +is_c_catch(#c_catch{}) -> + true; +is_c_catch(_) -> + false. + + +%% @spec catch_body(Node::cerl()) -> cerl() +%% +%% @doc Returns the body subtree of an abstract catch-expression. +%% +%% @see c_catch/1 + +-spec catch_body(c_catch()) -> cerl(). + +catch_body(Node) -> + Node#c_catch.body. + + +%% --------------------------------------------------------------------- + +%% @spec to_records(Tree::cerl()) -> record(record_types()) +%% +%% @doc Translates an abstract syntax tree to a corresponding explicit +%% record representation. The records are defined in the file +%% "cerl.hrl". +%% +%% @see type/1 +%% @see from_records/1 + +-spec to_records(cerl()) -> cerl(). + +to_records(Node) -> + Node. + +%% @spec from_records(Tree::record(record_types())) -> cerl() +%% +%% record_types() = c_alias | c_apply | c_call | c_case | c_catch | +%% c_clause | c_cons | c_fun | c_let | +%% c_letrec | c_lit | c_module | c_primop | +%% c_receive | c_seq | c_try | c_tuple | +%% c_values | c_var +%% +%% @doc Translates an explicit record representation to a +%% corresponding abstract syntax tree. The records are defined in the +%% file "core_parse.hrl". +%% +%% @see type/1 +%% @see to_records/1 + +-spec from_records(cerl()) -> cerl(). + +from_records(Node) -> + Node. + + +%% --------------------------------------------------------------------- + +%% @spec is_data(Node::cerl()) -> boolean() +%% +%% @doc Returns true if Node represents a +%% data constructor, otherwise false. Data constructors +%% are cons cells, tuples, and atomic literals. +%% +%% @see data_type/1 +%% @see data_es/1 +%% @see data_arity/1 + +-spec is_data(cerl()) -> boolean(). + +is_data(#c_literal{}) -> + true; +is_data(#c_cons{}) -> + true; +is_data(#c_tuple{}) -> + true; +is_data(_) -> + false. + + +%% @spec data_type(Node::cerl()) -> dtype() +%% +%% dtype() = cons | tuple | {atomic, Value} +%% Value = integer() | float() | atom() | [] +%% +%% @doc Returns a type descriptor for a data constructor +%% node. (Cf. is_data/1.) This is mainly useful for +%% comparing types and for constructing new nodes of the same type +%% (cf. make_data/2). If Node represents an +%% integer, floating-point number, atom or empty list, the result is +%% {atomic, Value}, where Value is the value +%% of concrete(Node), otherwise the result is either +%% cons or tuple. +%% +%%

Type descriptors can be compared for equality or order (in the +%% Erlang term order), but remember that floating-point values should +%% in general never be tested for equality.

+%% +%% @see is_data/1 +%% @see make_data/2 +%% @see type/1 +%% @see concrete/1 + +-type value() :: integer() | float() | atom() | []. +-type dtype() :: 'cons' | 'tuple' | {'atomic', value()}. +-type c_lct() :: c_literal() | c_cons() | c_tuple(). + +-spec data_type(c_lct()) -> dtype(). + +data_type(#c_literal{val = V}) -> + case V of + [_ | _] -> + cons; + _ when is_tuple(V) -> + tuple; + _ -> + {atomic, V} + end; +data_type(#c_cons{}) -> + cons; +data_type(#c_tuple{}) -> + tuple. + + +%% @spec data_es(Node::cerl()) -> [cerl()] +%% +%% @doc Returns the list of subtrees of a data constructor node. If +%% the arity of the constructor is zero, the result is the empty list. +%% +%%

Note: if data_type(Node) is cons, the +%% number of subtrees is exactly two. If data_type(Node) +%% is {atomic, Value}, the number of subtrees is +%% zero.

+%% +%% @see is_data/1 +%% @see data_type/1 +%% @see data_arity/1 +%% @see make_data/2 + +-spec data_es(c_lct()) -> [cerl()]. + +data_es(#c_literal{val = V}) -> + case V of + [Head | Tail] -> + [#c_literal{val = Head}, #c_literal{val = Tail}]; + _ when is_tuple(V) -> + make_lit_list(tuple_to_list(V)); + _ -> + [] + end; +data_es(#c_cons{hd = H, tl = T}) -> + [H, T]; +data_es(#c_tuple{es = Es}) -> + Es. + + +%% @spec data_arity(Node::cerl()) -> integer() +%% +%% @doc Returns the number of subtrees of a data constructor +%% node. This is equivalent to length(data_es(Node)), but +%% potentially more efficient. +%% +%% @see is_data/1 +%% @see data_es/1 + +-spec data_arity(c_lct()) -> non_neg_integer(). + +data_arity(#c_literal{val = V}) -> + case V of + [_ | _] -> + 2; + _ when is_tuple(V) -> + tuple_size(V); + _ -> + 0 + end; +data_arity(#c_cons{}) -> + 2; +data_arity(#c_tuple{es = Es}) -> + length(Es). + + +%% @spec make_data(Type::dtype(), Elements::[cerl()]) -> cerl() +%% +%% @doc Creates a data constructor node with the specified type and +%% subtrees. (Cf. data_type/1.) An exception is thrown +%% if the length of Elements is invalid for the given +%% Type; see data_es/1 for arity constraints +%% on constructor types. +%% +%% @see data_type/1 +%% @see data_es/1 +%% @see ann_make_data/3 +%% @see update_data/3 +%% @see make_data_skel/2 + +-spec make_data(dtype(), [cerl()]) -> c_lct(). + +make_data(CType, Es) -> + ann_make_data([], CType, Es). + + +%% @spec ann_make_data(As::[term()], Type::dtype(), +%% Elements::[cerl()]) -> cerl() +%% @see make_data/2 + +-spec ann_make_data([term()], dtype(), [cerl()]) -> c_lct(). + +ann_make_data(As, {atomic, V}, []) -> #c_literal{val = V, anno = As}; +ann_make_data(As, cons, [H, T]) -> ann_c_cons(As, H, T); +ann_make_data(As, tuple, Es) -> ann_c_tuple(As, Es). + + +%% @spec update_data(Old::cerl(), Type::dtype(), +%% Elements::[cerl()]) -> cerl() +%% @see make_data/2 + +-spec update_data(cerl(), dtype(), [cerl()]) -> c_lct(). + +update_data(Node, CType, Es) -> + ann_make_data(get_ann(Node), CType, Es). + + +%% @spec make_data_skel(Type::dtype(), Elements::[cerl()]) -> cerl() +%% +%% @doc Like make_data/2, but analogous to +%% c_tuple_skel/1 and c_cons_skel/2. +%% +%% @see ann_make_data_skel/3 +%% @see update_data_skel/3 +%% @see make_data/2 +%% @see c_tuple_skel/1 +%% @see c_cons_skel/2 + +-spec make_data_skel(dtype(), [cerl()]) -> c_lct(). + +make_data_skel(CType, Es) -> + ann_make_data_skel([], CType, Es). + + +%% @spec ann_make_data_skel(As::[term()], Type::dtype(), +%% Elements::[cerl()]) -> cerl() +%% @see make_data_skel/2 + +-spec ann_make_data_skel([term()], dtype(), [cerl()]) -> c_lct(). + +ann_make_data_skel(As, {atomic, V}, []) -> #c_literal{val = V, anno = As}; +ann_make_data_skel(As, cons, [H, T]) -> ann_c_cons_skel(As, H, T); +ann_make_data_skel(As, tuple, Es) -> ann_c_tuple_skel(As, Es). + + +%% @spec update_data_skel(Old::cerl(), Type::dtype(), +%% Elements::[cerl()]) -> cerl() +%% @see make_data_skel/2 + +-spec update_data_skel(cerl(), dtype(), [cerl()]) -> c_lct(). + +update_data_skel(Node, CType, Es) -> + ann_make_data_skel(get_ann(Node), CType, Es). + + +%% --------------------------------------------------------------------- + +%% @spec subtrees(Node::cerl()) -> [[cerl()]] +%% +%% @doc Returns the grouped list of all subtrees of a node. If +%% Node is a leaf node (cf. is_leaf/1), this +%% is the empty list, otherwise the result is always a nonempty list, +%% containing the lists of subtrees of Node, in +%% left-to-right order as they occur in the printed program text, and +%% grouped by category. Often, each group contains only a single +%% subtree. +%% +%%

Depending on the type of Node, the size of some +%% groups may be variable (e.g., the group consisting of all the +%% elements of a tuple), while others always contain the same number +%% of elements - usually exactly one (e.g., the group containing the +%% argument expression of a case-expression). Note, however, that the +%% exact structure of the returned list (for a given node type) should +%% in general not be depended upon, since it might be subject to +%% change without notice.

+%% +%%

The function subtrees/1 and the constructor functions +%% make_tree/2 and update_tree/2 can be a +%% great help if one wants to traverse a syntax tree, visiting all its +%% subtrees, but treat nodes of the tree in a uniform way in most or all +%% cases. Using these functions makes this simple, and also assures that +%% your code is not overly sensitive to extensions of the syntax tree +%% data type, because any node types not explicitly handled by your code +%% can be left to a default case.

+%% +%%

For example: +%% 

+%%   postorder(F, Tree) ->
+%%       F(case subtrees(Tree) of
+%%           [] -> Tree;
+%%           List -> update_tree(Tree,
+%%                               [[postorder(F, Subtree)
+%%                                 || Subtree <- Group]
+%%                                || Group <- List])
+%%         end).
+%%
+%% maps the function F on Tree and all its +%% subtrees, doing a post-order traversal of the syntax tree. (Note +%% the use of update_tree/2 to preserve annotations.) For +%% a simple function like: +%% 
+%%   f(Node) ->
+%%       case type(Node) of
+%%           atom -> atom("a_" ++ atom_name(Node));
+%%           _ -> Node
+%%       end.
+%%
+%% the call postorder(fun f/1, Tree) will yield a new +%% representation of Tree in which all atom names have +%% been extended with the prefix "a_", but nothing else (including +%% annotations) has been changed.

+%% +%% @see is_leaf/1 +%% @see make_tree/2 +%% @see update_tree/2 + +-spec subtrees(cerl()) -> [[cerl()]]. + +subtrees(T) -> + case is_leaf(T) of + true -> + []; + false -> + case type(T) of + values -> + [values_es(T)]; + binary -> + [binary_segments(T)]; + bitstr -> + [[bitstr_val(T)], [bitstr_size(T)], + [bitstr_unit(T)], [bitstr_type(T)], + [bitstr_flags(T)]]; + cons -> + [[cons_hd(T)], [cons_tl(T)]]; + tuple -> + [tuple_es(T)]; + 'let' -> + [let_vars(T), [let_arg(T)], [let_body(T)]]; + seq -> + [[seq_arg(T)], [seq_body(T)]]; + apply -> + [[apply_op(T)], apply_args(T)]; + call -> + [[call_module(T)], [call_name(T)], + call_args(T)]; + primop -> + [[primop_name(T)], primop_args(T)]; + 'case' -> + [[case_arg(T)], case_clauses(T)]; + clause -> + [clause_pats(T), [clause_guard(T)], + [clause_body(T)]]; + alias -> + [[alias_var(T)], [alias_pat(T)]]; + 'fun' -> + [fun_vars(T), [fun_body(T)]]; + 'receive' -> + [receive_clauses(T), [receive_timeout(T)], + [receive_action(T)]]; + 'try' -> + [[try_arg(T)], try_vars(T), [try_body(T)], + try_evars(T), [try_handler(T)]]; + 'catch' -> + [[catch_body(T)]]; + letrec -> + Es = unfold_tuples(letrec_defs(T)), + [Es, [letrec_body(T)]]; + module -> + As = unfold_tuples(module_attrs(T)), + Es = unfold_tuples(module_defs(T)), + [[module_name(T)], module_exports(T), As, Es] + end + end. + + +%% @spec update_tree(Old::cerl(), Groups::[[cerl()]]) -> cerl() +%% +%% @doc Creates a syntax tree with the given subtrees, and the same +%% type and annotations as the Old node. This is +%% equivalent to ann_make_tree(get_ann(Node), type(Node), +%% Groups), but potentially more efficient. +%% +%% @see update_tree/3 +%% @see ann_make_tree/3 +%% @see get_ann/1 +%% @see type/1 + +-spec update_tree(cerl(), [[cerl()],...]) -> cerl(). + +update_tree(Node, Gs) -> + ann_make_tree(get_ann(Node), type(Node), Gs). + + +%% @spec update_tree(Old::cerl(), Type::ctype(), Groups::[[cerl()]]) -> +%% cerl() +%% +%% @doc Creates a syntax tree with the given type and subtrees, and +%% the same annotations as the Old node. This is +%% equivalent to ann_make_tree(get_ann(Node), Type, +%% Groups), but potentially more efficient. +%% +%% @see update_tree/2 +%% @see ann_make_tree/3 +%% @see get_ann/1 + +-spec update_tree(cerl(), ctype(), [[cerl()],...]) -> cerl(). + +update_tree(Node, Type, Gs) -> + ann_make_tree(get_ann(Node), Type, Gs). + + +%% @spec make_tree(Type::ctype(), Groups::[[cerl()]]) -> cerl() +%% +%% @doc Creates a syntax tree with the given type and subtrees. +%% Type must be a node type name +%% (cf. type/1) that does not denote a leaf node type +%% (cf. is_leaf/1). Groups must be a +%% nonempty list of groups of syntax trees, representing the +%% subtrees of a node of the given type, in left-to-right order as +%% they would occur in the printed program text, grouped by category +%% as done by subtrees/1. +%% +%%

The result of ann_make_tree(get_ann(Node), type(Node), +%% subtrees(Node)) (cf. update_tree/2) represents +%% the same source code text as the original Node, +%% assuming that subtrees(Node) yields a nonempty +%% list. However, it does not necessarily have the exact same data +%% representation as Node.

+%% +%% @see ann_make_tree/3 +%% @see type/1 +%% @see is_leaf/1 +%% @see subtrees/1 +%% @see update_tree/2 + +-spec make_tree(ctype(), [[cerl()],...]) -> cerl(). + +make_tree(Type, Gs) -> + ann_make_tree([], Type, Gs). + + +%% @spec ann_make_tree(As::[term()], Type::ctype(), +%% Groups::[[cerl()]]) -> cerl() +%% +%% @doc Creates a syntax tree with the given annotations, type and +%% subtrees. See make_tree/2 for details. +%% +%% @see make_tree/2 + +-spec ann_make_tree([term()], ctype(), [[cerl()],...]) -> cerl(). + +ann_make_tree(As, values, [Es]) -> ann_c_values(As, Es); +ann_make_tree(As, binary, [Ss]) -> ann_c_binary(As, Ss); +ann_make_tree(As, bitstr, [[V],[S],[U],[T],[Fs]]) -> + ann_c_bitstr(As, V, S, U, T, Fs); +ann_make_tree(As, cons, [[H], [T]]) -> ann_c_cons(As, H, T); +ann_make_tree(As, tuple, [Es]) -> ann_c_tuple(As, Es); +ann_make_tree(As, 'let', [Vs, [A], [B]]) -> ann_c_let(As, Vs, A, B); +ann_make_tree(As, seq, [[A], [B]]) -> ann_c_seq(As, A, B); +ann_make_tree(As, apply, [[Op], Es]) -> ann_c_apply(As, Op, Es); +ann_make_tree(As, call, [[M], [N], Es]) -> ann_c_call(As, M, N, Es); +ann_make_tree(As, primop, [[N], Es]) -> ann_c_primop(As, N, Es); +ann_make_tree(As, 'case', [[A], Cs]) -> ann_c_case(As, A, Cs); +ann_make_tree(As, clause, [Ps, [G], [B]]) -> ann_c_clause(As, Ps, G, B); +ann_make_tree(As, alias, [[V], [P]]) -> ann_c_alias(As, V, P); +ann_make_tree(As, 'fun', [Vs, [B]]) -> ann_c_fun(As, Vs, B); +ann_make_tree(As, 'receive', [Cs, [T], [A]]) -> + ann_c_receive(As, Cs, T, A); +ann_make_tree(As, 'try', [[E], Vs, [B], Evs, [H]]) -> + ann_c_try(As, E, Vs, B, Evs, H); +ann_make_tree(As, 'catch', [[B]]) -> ann_c_catch(As, B); +ann_make_tree(As, letrec, [Es, [B]]) -> + ann_c_letrec(As, fold_tuples(Es), B); +ann_make_tree(As, module, [[N], Xs, Es, Ds]) -> + ann_c_module(As, N, Xs, fold_tuples(Es), fold_tuples(Ds)). + + +%% --------------------------------------------------------------------- + +%% @spec meta(Tree::cerl()) -> cerl() +%% +%% @doc Creates a meta-representation of a syntax tree. The result +%% represents an Erlang expression "MetaTree" +%% which, if evaluated, will yield a new syntax tree representing the +%% same source code text as Tree (although the actual +%% data representation may be different). The expression represented +%% by MetaTree is implementation independent +%% with regard to the data structures used by the abstract syntax tree +%% implementation. +%% +%%

Any node in Tree whose node type is +%% var (cf. type/1), and whose list of +%% annotations (cf. get_ann/1) contains the atom +%% meta_var, will remain unchanged in the resulting tree, +%% except that exactly one occurrence of meta_var is +%% removed from its annotation list.

+%% +%%

The main use of the function meta/1 is to transform +%% a data structure Tree, which represents a piece of +%% program code, into a form that is representation independent +%% when printed. E.g., suppose Tree represents a +%% variable named "V". Then (assuming a function print/1 +%% for printing syntax trees), evaluating +%% print(abstract(Tree)) - simply using +%% abstract/1 to map the actual data structure onto a +%% syntax tree representation - would output a string that might look +%% something like "{var, ..., 'V'}", which is obviously +%% dependent on the implementation of the abstract syntax trees. This +%% could e.g. be useful for caching a syntax tree in a file. However, +%% in some situations like in a program generator generator (with two +%% "generator"), it may be unacceptable. Using +%% print(meta(Tree)) instead would output a +%% representation independent syntax tree generating +%% expression; in the above case, something like +%% "cerl:c_var('V')".

+%% +%%

The implementation tries to generate compact code with respect +%% to literals and lists.

+%% +%% @see abstract/1 +%% @see type/1 +%% @see get_ann/1 + +-spec meta(cerl()) -> cerl(). + +meta(Node) -> + %% First of all we check for metavariables: + case type(Node) of + var -> + case lists:member(meta_var, get_ann(Node)) of + false -> + meta_0(var, Node); + true -> + %% A meta-variable: remove the first found + %% 'meta_var' annotation, but otherwise leave + %% the node unchanged. + set_ann(Node, lists:delete(meta_var, get_ann(Node))) + end; + Type -> + meta_0(Type, Node) + end. + +meta_0(Type, Node) -> + case get_ann(Node) of + [] -> + meta_1(Type, Node); + As -> + meta_call(set_ann, [meta_1(Type, Node), abstract(As)]) + end. + +meta_1(literal, Node) -> + %% We handle atomic literals separately, to get a bit + %% more compact code. For the rest, we use 'abstract'. + case concrete(Node) of + V when is_atom(V) -> + meta_call(c_atom, [Node]); + V when is_integer(V) -> + meta_call(c_int, [Node]); + V when is_float(V) -> + meta_call(c_float, [Node]); + [] -> + meta_call(c_nil, []); + _ -> + meta_call(abstract, [Node]) + end; +meta_1(var, Node) -> + %% A normal variable or function name. + meta_call(c_var, [abstract(var_name(Node))]); +meta_1(values, Node) -> + meta_call(c_values, + [make_list(meta_list(values_es(Node)))]); +meta_1(binary, Node) -> + meta_call(c_binary, + [make_list(meta_list(binary_segments(Node)))]); +meta_1(bitstr, Node) -> + meta_call(c_bitstr, + [meta(bitstr_val(Node)), + meta(bitstr_size(Node)), + meta(bitstr_unit(Node)), + meta(bitstr_type(Node)), + meta(bitstr_flags(Node))]); +meta_1(cons, Node) -> + %% The list is split up if some sublist has annotatations. If + %% we get exactly one element, we generate a 'c_cons' call + %% instead of 'make_list' to reconstruct the node. + case split_list(Node) of + {[H], none} -> + meta_call(c_cons, [meta(H), meta(c_nil())]); + {[H], Node1} -> + meta_call(c_cons, [meta(H), meta(Node1)]); + {L, none} -> + meta_call(make_list, [make_list(meta_list(L))]); + {L, Node1} -> + meta_call(make_list, + [make_list(meta_list(L)), meta(Node1)]) + end; +meta_1(tuple, Node) -> + meta_call(c_tuple, + [make_list(meta_list(tuple_es(Node)))]); +meta_1('let', Node) -> + meta_call(c_let, + [make_list(meta_list(let_vars(Node))), + meta(let_arg(Node)), meta(let_body(Node))]); +meta_1(seq, Node) -> + meta_call(c_seq, + [meta(seq_arg(Node)), meta(seq_body(Node))]); +meta_1(apply, Node) -> + meta_call(c_apply, + [meta(apply_op(Node)), + make_list(meta_list(apply_args(Node)))]); +meta_1(call, Node) -> + meta_call(c_call, + [meta(call_module(Node)), meta(call_name(Node)), + make_list(meta_list(call_args(Node)))]); +meta_1(primop, Node) -> + meta_call(c_primop, + [meta(primop_name(Node)), + make_list(meta_list(primop_args(Node)))]); +meta_1('case', Node) -> + meta_call(c_case, + [meta(case_arg(Node)), + make_list(meta_list(case_clauses(Node)))]); +meta_1(clause, Node) -> + meta_call(c_clause, + [make_list(meta_list(clause_pats(Node))), + meta(clause_guard(Node)), + meta(clause_body(Node))]); +meta_1(alias, Node) -> + meta_call(c_alias, + [meta(alias_var(Node)), meta(alias_pat(Node))]); +meta_1('fun', Node) -> + meta_call(c_fun, + [make_list(meta_list(fun_vars(Node))), + meta(fun_body(Node))]); +meta_1('receive', Node) -> + meta_call(c_receive, + [make_list(meta_list(receive_clauses(Node))), + meta(receive_timeout(Node)), + meta(receive_action(Node))]); +meta_1('try', Node) -> + meta_call(c_try, + [meta(try_arg(Node)), + make_list(meta_list(try_vars(Node))), + meta(try_body(Node)), + make_list(meta_list(try_evars(Node))), + meta(try_handler(Node))]); +meta_1('catch', Node) -> + meta_call(c_catch, [meta(catch_body(Node))]); +meta_1(letrec, Node) -> + meta_call(c_letrec, + [make_list([c_tuple([meta(N), meta(F)]) + || {N, F} <- letrec_defs(Node)]), + meta(letrec_body(Node))]); +meta_1(module, Node) -> + meta_call(c_module, + [meta(module_name(Node)), + make_list(meta_list(module_exports(Node))), + make_list([c_tuple([meta(A), meta(V)]) + || {A, V} <- module_attrs(Node)]), + make_list([c_tuple([meta(N), meta(F)]) + || {N, F} <- module_defs(Node)])]). + +meta_call(F, As) -> + c_call(c_atom(?MODULE), c_atom(F), As). + +meta_list([T | Ts]) -> + [meta(T) | meta_list(Ts)]; +meta_list([]) -> + []. + +split_list(Node) -> + split_list(set_ann(Node, []), []). + +split_list(Node, L) -> + A = get_ann(Node), + case type(Node) of + cons when A =:= [] -> + split_list(cons_tl(Node), [cons_hd(Node) | L]); + nil when A =:= [] -> + {lists:reverse(L), none}; + _ -> + {lists:reverse(L), Node} + end. + + +%% --------------------------------------------------------------------- + +%% General utilities + +is_lit_list([#c_literal{} | Es]) -> + is_lit_list(Es); +is_lit_list([_ | _]) -> + false; +is_lit_list([]) -> + true. + +lit_list_vals([#c_literal{val = V} | Es]) -> + [V | lit_list_vals(Es)]; +lit_list_vals([]) -> + []. + +-spec make_lit_list([_]) -> [#c_literal{}]. % XXX: cerl() instead of _ ? + +make_lit_list([V | Vs]) -> + [#c_literal{val = V} | make_lit_list(Vs)]; +make_lit_list([]) -> + []. + +%% The following tests are the same as done by 'io_lib:char_list' and +%% 'io_lib:printable_list', respectively, but for a single character. + +is_char_value(V) when V >= $\000, V =< $\377 -> true; +is_char_value(_) -> false. + +is_print_char_value(V) when V >= $\040, V =< $\176 -> true; +is_print_char_value(V) when V >= $\240, V =< $\377 -> true; +is_print_char_value(V) when V =:= $\b -> true; +is_print_char_value(V) when V =:= $\d -> true; +is_print_char_value(V) when V =:= $\e -> true; +is_print_char_value(V) when V =:= $\f -> true; +is_print_char_value(V) when V =:= $\n -> true; +is_print_char_value(V) when V =:= $\r -> true; +is_print_char_value(V) when V =:= $\s -> true; +is_print_char_value(V) when V =:= $\t -> true; +is_print_char_value(V) when V =:= $\v -> true; +is_print_char_value(V) when V =:= $\" -> true; +is_print_char_value(V) when V =:= $\' -> true; +is_print_char_value(V) when V =:= $\\ -> true; +is_print_char_value(_) -> false. + +is_char_list([V | Vs]) when is_integer(V) -> + is_char_value(V) andalso is_char_list(Vs); +is_char_list([]) -> + true; +is_char_list(_) -> + false. + +is_print_char_list([V | Vs]) when is_integer(V) -> + is_print_char_value(V) andalso is_print_char_list(Vs); +is_print_char_list([]) -> + true; +is_print_char_list(_) -> + false. + +unfold_tuples([{X, Y} | Ps]) -> + [X, Y | unfold_tuples(Ps)]; +unfold_tuples([]) -> + []. + +fold_tuples([X, Y | Es]) -> + [{X, Y} | fold_tuples(Es)]; +fold_tuples([]) -> + []. -- cgit v1.2.3