erl_parse

19962016 Ericsson AB. 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. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. erl_parse Robert Bjarne Däcker 1 Bjarne Däcker 1997-01-24 B erl_parse.xml

erl_parse The Erlang parser.

This module is the basic Erlang parser that converts tokens into the abstract form of either forms (that is, top-level constructs), expressions, or terms. The Abstract Format is described in the ERTS User's Guide. Notice that a token list must end with the dot token to be acceptable to the parse functions (see the erl_scan(3)) module.

abstract_clause()

Abstract form of an Erlang clause.

abstract_expr()

Abstract form of an Erlang expression.

abstract_form()

Abstract form of an Erlang form.

abstract_type()

Abstract form of an Erlang type.

Tuples {error, error_info()} and {warning, error_info()}, denoting syntactically incorrect forms and warnings, and {eof, line()}, denoting an end-of-stream encountered before a complete form had been parsed.

Convert an Erlang term into an abstract form.

Converts the Erlang data structure Data into an abstract form of type AbsTerm. This function is the inverse of normalise/1.

erl_parse:abstract(T) is equivalent to erl_parse:abstract(T, 0).

Convert an Erlang term into an abstract form.

Converts the Erlang data structure Data into an abstract form of type AbsTerm.

Option Line is the line to be assigned to each node of AbsTerm.

Option Encoding is used for selecting which integer lists to be considered as strings. The default is to use the encoding returned by function epp:default_encoding/0. Value none means that no integer lists are considered as strings. encoding_func() is called with one integer of a list at a time; if it returns true for every integer, the list is considered a string.

Return annotations as terms.

Assumes that Term is a term with the same structure as a erl_parse tree, but with terms, say T, where a erl_parse tree has collections of annotations. Returns a erl_parse tree where each term T is replaced by the value returned by erl_anno:from_term(T). The term Term is traversed in a depth-first, left-to-right fashion.

Return the representation of annotations.

Returns a term where each collection of annotations Anno of the nodes of the erl_parse tree Abstr is replaced by the term returned by erl_anno:to_term(Anno). The erl_parse tree is traversed in a depth-first, left-to-right fashion.

Fold a function over the annotations of an erl_parse tree.

Updates an accumulator by applying Fun on each collection of annotations of the erl_parse tree Abstr. The first call to Fun has AccIn as argument, the returned accumulator AccOut is passed to the next call, and so on. The final value of the accumulator is returned. The erl_parse tree is traversed in a depth-first, left-to-right fashion.

format_error(ErrorDescriptor) -> Chars Format an error descriptor. ErrorDescriptor = error_description() Chars = [char() | Chars]

Uses an ErrorDescriptor and returns a string that describes the error. This function is usually called implicitly when an ErrorInfo structure is processed (see section Error Information).

Map a function over the annotations of an erl_parse tree.

Modifies the erl_parse tree Abstr by applying Fun on each collection of annotations of the nodes of the erl_parse tree. The erl_parse tree is traversed in a depth-first, left-to-right fashion.

Map and fold a function over the annotations of an erl_parse tree.

Modifies the erl_parse tree Abstr by applying Fun on each collection of annotations of the nodes of the erl_parse tree, while at the same time updating an accumulator. The first call to Fun has AccIn as second argument, the returned accumulator AccOut is passed to the next call, and so on. The modified erl_parse tree and the final value of the accumulator are returned. The erl_parse tree is traversed in a depth-first, left-to-right fashion.

Create new annotations.

Assumes that Term is a term with the same structure as a erl_parse tree, but with locations where a erl_parse tree has collections of annotations. Returns a erl_parse tree where each location L is replaced by the value returned by erl_anno:new(L). The term Term is traversed in a depth-first, left-to-right fashion.

Convert abstract form to an Erlang term.

Converts the abstract form AbsTerm of a term into a conventional Erlang data structure (that is, the term itself). This function is the inverse of abstract/1.

Parse Erlang expressions.

Parses Tokens as if it was a list of expressions. Returns one of the following:

{ok, ExprList}

The parsing was successful. ExprList is a list of the abstract forms of the parsed expressions.

{error, ErrorInfo}

An error occurred.

Parse an Erlang form.

Parses Tokens as if it was a form. Returns one of the following:

{ok, AbsForm}

The parsing was successful. AbsForm is the abstract form of the parsed form.

{error, ErrorInfo}

An error occurred.

Parse an Erlang term.

Parses Tokens as if it was a term. Returns one of the following:

{ok, Term}

The parsing was successful. Term is the Erlang term corresponding to the token list.

{error, ErrorInfo}

An error occurred.

Generate a list of tokens for an expression.

Generates a list of tokens representing the abstract form AbsTerm of an expression. Optionally, MoreTokens is appended.

Error Information

ErrorInfo is the standard ErrorInfo structure that is returned from all I/O modules. The format is as follows:


{ErrorLine, Module, ErrorDescriptor}

A string describing the error is obtained with the following call:


Module:format_error(ErrorDescriptor)