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.
Functions
open(FileName, IncludePath) -> {ok,Epp} | {error, ErrorDescriptor}
open(FileName, IncludePath, PredefMacros) -> {ok,Epp} | {error, ErrorDescriptor}
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
Epp = pid() -- handle to the epp server
Closes the preprocessing of a file.
parse_erl_form(Epp) -> {ok, AbsForm} | {eof, Line} | {error, ErrorInfo}
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}
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)