epp

1996 2007 Ericsson AB, 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. The Initial Developer of the Original Code is Ericsson AB. epp Kenneth Lundin Kenneth Lundin 1 Kenneth Lundin 97-01-31 B epp.sgml

epp An Erlang Code Preprocessor

The Erlang code preprocessor includes functions which are used by compile to preprocess macros and include files before the actual parsing takes place.

open(FileName, IncludePath) -> {ok,Epp} | {error, ErrorDescriptor} open(FileName, IncludePath, PredefMacros) -> {ok,Epp} | {error, ErrorDescriptor} Open a file for preprocessing FileName = atom() | string() IncludePath = [DirectoryName] DirectoryName = atom() | string() PredefMacros = [{atom(),term()}] Epp = pid() -- handle to the epp server ErrorDescriptor = term()

Opens a file for preprocessing.

close(Epp) -> ok Close the preprocessing of the file associated with Epp Epp = pid() -- handle to the epp server

Closes the preprocessing of a file.

parse_erl_form(Epp) -> {ok, AbsForm} | {eof, Line} | {error, ErrorInfo} Return the next Erlang form from the opened Erlang source file Epp = pid() AbsForm = term() Line = integer() ErrorInfo = see separate description below.

Returns the next Erlang form from the opened Erlang source file. The tuple {eof, Line} is returned at end-of-file. The first form corresponds to an implicit attribute -file(File,1)., where File is the name of the file.

parse_file(FileName,IncludePath,PredefMacro) -> {ok,[Form]} | {error,OpenError} Preprocesse and parse an Erlang source file FileName = atom() | string() IncludePath = [DirectoryName] DirectoryName = atom() | string() PredefMacros = [{atom(),term()}] Form = term() -- same as returned by erl_parse:parse_form

Preprocesses and parses an Erlang source file. Note that the tuple {eof, Line} returned at end-of-file is included as a "form".

Error Information

The ErrorInfo mentioned above is the standard ErrorInfo structure which is returned from all IO modules. It has the following format:


    {ErrorLine, Module, ErrorDescriptor}

A string which describes the error is obtained with the following call:


apply(Module, format_error, ErrorDescriptor)