diff options
Diffstat (limited to 'lib/stdlib/src/io_lib.erl')
| -rw-r--r-- | lib/stdlib/src/io_lib.erl | 230 |
1 files changed, 190 insertions, 40 deletions
diff --git a/lib/stdlib/src/io_lib.erl b/lib/stdlib/src/io_lib.erl index ad98bc0420..50bf959db5 100644 --- a/lib/stdlib/src/io_lib.erl +++ b/lib/stdlib/src/io_lib.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2016. All Rights Reserved. +%% Copyright Ericsson AB 1996-2018. All Rights Reserved. %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. @@ -28,7 +28,7 @@ %% Most of the code here is derived from the original prolog versions and %% from similar code written by Joe Armstrong and myself. %% -%% This module has been split into seperate modules: +%% This module has been split into separate modules: %% io_lib - basic write and utilities %% io_lib_format - formatted output %% io_lib_fread - formatted input @@ -68,8 +68,8 @@ -export([write_atom/1,write_string/1,write_string/2,write_latin1_string/1, write_latin1_string/2, write_char/1, write_latin1_char/1]). --export([write_string_as_latin1/1, write_string_as_latin1/2, - write_char_as_latin1/1]). +-export([write_atom_as_latin1/1, write_string_as_latin1/1, + write_string_as_latin1/2, write_char_as_latin1/1]). -export([quote_atom/2, char_list/1, latin1_char_list/1, deep_char_list/1, deep_latin1_char_list/1, @@ -84,6 +84,8 @@ -export([write_unicode_string/1, write_unicode_char/1, deep_unicode_char_list/1]). +-export([limit_term/2]). + -export_type([chars/0, latin1_string/0, continuation/0, fread_error/0, fread_item/0, format_spec/0]). @@ -147,7 +149,7 @@ fread(Chars, Format) -> -spec fread(Continuation, CharSpec, Format) -> Return when Continuation :: continuation() | [], - CharSpec :: string() | eof, + CharSpec :: string() | 'eof', Format :: string(), Return :: {'more', Continuation1 :: continuation()} | {'done', Result, LeftOverChars :: string()}, @@ -268,47 +270,61 @@ write(Term, D, false) -> -spec write(Term, Depth) -> chars() when Term :: term(), + Depth :: depth(); + (Term, Options) -> chars() when + Term :: term(), + Options :: [Option], + Option :: {'depth', Depth} + | {'encoding', 'latin1' | 'utf8' | 'unicode'}, Depth :: depth(). -write(_Term, 0) -> "..."; -write(Term, _D) when is_integer(Term) -> integer_to_list(Term); -write(Term, _D) when is_float(Term) -> io_lib_format:fwrite_g(Term); -write(Atom, _D) when is_atom(Atom) -> write_atom(Atom); -write(Term, _D) when is_port(Term) -> write_port(Term); -write(Term, _D) when is_pid(Term) -> pid_to_list(Term); -write(Term, _D) when is_reference(Term) -> write_ref(Term); -write(<<_/bitstring>>=Term, D) -> write_binary(Term, D); -write([], _D) -> "[]"; -write({}, _D) -> "{}"; -write([H|T], D) -> +write(Term, Options) when is_list(Options) -> + Depth = get_option(depth, Options, -1), + Encoding = get_option(encoding, Options, epp:default_encoding()), + write1(Term, Depth, Encoding); +write(Term, Depth) -> + write1(Term, Depth, latin1). + +write1(_Term, 0, _E) -> "..."; +write1(Term, _D, _E) when is_integer(Term) -> integer_to_list(Term); +write1(Term, _D, _E) when is_float(Term) -> io_lib_format:fwrite_g(Term); +write1(Atom, _D, latin1) when is_atom(Atom) -> write_atom_as_latin1(Atom); +write1(Atom, _D, _E) when is_atom(Atom) -> write_atom(Atom); +write1(Term, _D, _E) when is_port(Term) -> write_port(Term); +write1(Term, _D, _E) when is_pid(Term) -> pid_to_list(Term); +write1(Term, _D, _E) when is_reference(Term) -> write_ref(Term); +write1(<<_/bitstring>>=Term, D, _E) -> write_binary(Term, D); +write1([], _D, _E) -> "[]"; +write1({}, _D, _E) -> "{}"; +write1([H|T], D, E) -> if D =:= 1 -> "[...]"; true -> - [$[,[write(H, D-1)|write_tail(T, D-1, $|)],$]] + [$[,[write1(H, D-1, E)|write_tail(T, D-1, E, $|)],$]] end; -write(F, _D) when is_function(F) -> +write1(F, _D, _E) when is_function(F) -> erlang:fun_to_list(F); -write(Term, D) when is_map(Term) -> - write_map(Term, D); -write(T, D) when is_tuple(T) -> +write1(Term, D, E) when is_map(Term) -> + write_map(Term, D, E); +write1(T, D, E) when is_tuple(T) -> if D =:= 1 -> "{...}"; true -> [${, - [write(element(1, T), D-1)| - write_tail(tl(tuple_to_list(T)), D-1, $,)], + [write1(element(1, T), D-1, E)| + write_tail(tl(tuple_to_list(T)), D-1, E, $,)], $}] end. %% write_tail(List, Depth, CharacterBeforeDots) %% Test the terminating case first as this looks better with depth. -write_tail([], _D, _S) -> ""; -write_tail(_, 1, S) -> [S | "..."]; -write_tail([H|T], D, S) -> - [$,,write(H, D-1)|write_tail(T, D-1, S)]; -write_tail(Other, D, S) -> - [S,write(Other, D-1)]. +write_tail([], _D, _E, _S) -> ""; +write_tail(_, 1, _E, S) -> [S | "..."]; +write_tail([H|T], D, E, S) -> + [$,,write1(H, D-1, E)|write_tail(T, D-1, E, S)]; +write_tail(Other, D, E, S) -> + [S,write1(Other, D-1, E)]. write_port(Port) -> erlang:port_to_list(Port). @@ -316,17 +332,17 @@ write_port(Port) -> write_ref(Ref) -> erlang:ref_to_list(Ref). -write_map(Map, D) when is_integer(D) -> - [$#,${,write_map_body(maps:to_list(Map), D),$}]. +write_map(Map, D, E) when is_integer(D) -> + [$#,${,write_map_body(maps:to_list(Map), D, E),$}]. -write_map_body(_, 0) -> "..."; -write_map_body([],_) -> []; -write_map_body([{K,V}],D) -> write_map_assoc(K,V,D); -write_map_body([{K,V}|KVs], D) -> - [write_map_assoc(K,V,D),$, | write_map_body(KVs,D-1)]. +write_map_body(_, 0, _E) -> "..."; +write_map_body([], _, _E) -> []; +write_map_body([{K,V}], D, E) -> write_map_assoc(K, V, D, E); +write_map_body([{K,V}|KVs], D, E) -> + [write_map_assoc(K, V, D, E),$, | write_map_body(KVs, D-1, E)]. -write_map_assoc(K,V,D) -> - [write(K,D - 1),"=>",write(V,D-1)]. +write_map_assoc(K, V, D, E) -> + [write1(K, D - 1, E),"=>",write1(V, D-1, E)]. write_binary(B, D) when is_integer(D) -> [$<,$<,write_binary_body(B, D),$>,$>]. @@ -344,6 +360,18 @@ write_binary_body(B, _D) -> <<X:L>> = B, [integer_to_list(X),$:,integer_to_list(L)]. +get_option(Key, TupleList, Default) -> + case lists:keyfind(Key, 1, TupleList) of + false -> Default; + {Key, Value} -> Value; + _ -> Default + end. + +%%% There are two functions to write Unicode atoms: +%%% - they both escape control characters < 160; +%%% - write_atom() never escapes characters >= 160; +%%% - write_atom_as_latin1() also escapes characters >= 255. + %% write_atom(Atom) -> [Char] %% Generate the list of characters needed to print an atom. @@ -351,17 +379,26 @@ write_binary_body(B, _D) -> Atom :: atom(). write_atom(Atom) -> + write_possibly_quoted_atom(Atom, fun write_string/2). + +-spec write_atom_as_latin1(Atom) -> latin1_string() when + Atom :: atom(). + +write_atom_as_latin1(Atom) -> + write_possibly_quoted_atom(Atom, fun write_string_as_latin1/2). + +write_possibly_quoted_atom(Atom, PFun) -> Chars = atom_to_list(Atom), case quote_atom(Atom, Chars) of true -> - write_string(Chars, $'); %' + PFun(Chars, $'); %' false -> Chars end. %% quote_atom(Atom, CharList) %% Return 'true' if atom with chars in CharList needs to be quoted, else -%% return 'false'. +%% return 'false'. Notice that characters >= 160 are always quoted. -spec quote_atom(atom(), chars()) -> boolean(). @@ -876,3 +913,116 @@ binrev(L) -> binrev(L, T) -> list_to_binary(lists:reverse(L, T)). + +-spec limit_term(term(), non_neg_integer()) -> term(). + +%% The intention is to mimic the depth limitation of io_lib:write() +%% and io_lib_pretty:print(). The leaves ('...') should never be +%% seen when printed with the same depth. Bitstrings are never +%% truncated, which is OK as long as they are not sent to other nodes. +limit_term(Term, Depth) -> + try test_limit(Term, Depth) of + ok -> Term + catch + throw:limit -> + limit(Term, Depth) + end. + +limit(_, 0) -> '...'; +limit([H|T]=L, D) -> + if + D =:= 1 -> '...'; + true -> + case printable_list(L) of + true -> L; + false -> + [limit(H, D-1)|limit_tail(T, D-1)] + end + end; +limit(Term, D) when is_map(Term) -> + limit_map(Term, D); +limit({}=T, _D) -> T; +limit(T, D) when is_tuple(T) -> + if + D =:= 1 -> '...'; + true -> + list_to_tuple([limit(element(1, T), D-1)| + limit_tail(tl(tuple_to_list(T)), D-1)]) + end; +limit(<<_/bitstring>>=Term, D) -> limit_bitstring(Term, D); +limit(Term, _D) -> Term. + +limit_tail([], _D) -> []; +limit_tail(_, 1) -> ['...']; +limit_tail([H|T], D) -> + [limit(H, D-1)|limit_tail(T, D-1)]; +limit_tail(Other, D) -> + limit(Other, D-1). + +%% Cannot limit maps properly since there is no guarantee that +%% maps:from_list() creates a map with the same internal ordering of +%% the selected associations as in Map. +limit_map(Map, D) -> + maps:from_list(erts_internal:maps_to_list(Map, D)). +%% maps:from_list(limit_map_body(erts_internal:maps_to_list(Map, D), D)). + +%% limit_map_body(_, 0) -> [{'...', '...'}]; +%% limit_map_body([], _) -> []; +%% limit_map_body([{K,V}], D) -> [limit_map_assoc(K, V, D)]; +%% limit_map_body([{K,V}|KVs], D) -> +%% [limit_map_assoc(K, V, D) | limit_map_body(KVs, D-1)]. + +%% limit_map_assoc(K, V, D) -> +%% {limit(K, D-1), limit(V, D-1)}. + +limit_bitstring(B, _D) -> B. %% Keeps all printable binaries. + +test_limit(_, 0) -> throw(limit); +test_limit([H|T]=L, D) when is_integer(D) -> + if + D =:= 1 -> throw(limit); + true -> + case printable_list(L) of + true -> ok; + false -> + test_limit(H, D-1), + test_limit_tail(T, D-1) + end + end; +test_limit(Term, D) when is_map(Term) -> + test_limit_map(Term, D); +test_limit({}, _D) -> ok; +test_limit(T, D) when is_tuple(T) -> + test_limit_tuple(T, 1, tuple_size(T), D); +test_limit(<<_/bitstring>>=Term, D) -> test_limit_bitstring(Term, D); +test_limit(_Term, _D) -> ok. + +test_limit_tail([], _D) -> ok; +test_limit_tail(_, 1) -> throw(limit); +test_limit_tail([H|T], D) -> + test_limit(H, D-1), + test_limit_tail(T, D-1); +test_limit_tail(Other, D) -> + test_limit(Other, D-1). + +test_limit_tuple(_T, I, Sz, _D) when I > Sz -> ok; +test_limit_tuple(_, _, _, 1) -> throw(limit); +test_limit_tuple(T, I, Sz, D) -> + test_limit(element(I, T), D-1), + test_limit_tuple(T, I+1, Sz, D-1). + +test_limit_map(_Map, _D) -> ok. +%% test_limit_map_body(erts_internal:maps_to_list(Map, D), D). + +%% test_limit_map_body(_, 0) -> throw(limit); +%% test_limit_map_body([], _) -> ok; +%% test_limit_map_body([{K,V}], D) -> test_limit_map_assoc(K, V, D); +%% test_limit_map_body([{K,V}|KVs], D) -> +%% test_limit_map_assoc(K, V, D), +%% test_limit_map_body(KVs, D-1). + +%% test_limit_map_assoc(K, V, D) -> +%% test_limit(K, D-1), +%% test_limit(V, D-1). + +test_limit_bitstring(_, _) -> ok. |