epp - An Erlang code preprocessor.

macros() =
           [atom() | {atom(), term()} | {atom(), term(), redefine}]

       epp_handle() = pid()

              Handle to the epp server.

       source_encoding() = latin1 | utf8

       warning_info() = {erl_anno:location(), module(), term()}

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

       The Erlang source file encoding is selected by a comment in one of the first  two  lines  of  the  source
       file.  The  first  string  matching  the  regular  expression coding\s*[:=]\s*([-a-zA-Z0-9])+ selects the
       encoding. If the matching string is not a valid encoding, it is ignored. The valid encodings are  Latin-1
       and UTF-8, where the case of the characters can be chosen freely.

       Examples:

       %% coding: utf-8

       %% For this file we have chosen encoding = Latin-1

       %% -*- coding: latin-1 -*-

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)

close(Epp)->ok

              Types:

                 Epp = epp_handle()

              Closes the preprocessing of a file.

       default_encoding()->source_encoding()

              Returns the default encoding of Erlang source files.

       encoding_to_string(Encoding)->string()

              Types:

                 Encoding = source_encoding()

              Returns  a  string  representation  of an encoding. The string is recognized by read_encoding/1,2,
              read_encoding_from_binary/1,2, and set_encoding/1,2 as a valid encoding.

       format_error(ErrorDescriptor)->io_lib:chars()

              Types:

                 ErrorDescriptor = term()

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

       open(Options)->
               {ok, Epp} | {ok, Epp, Extra} | {error, ErrorDescriptor}

              Types:

                 Options =
                     [{default_encoding, DefEncoding :: source_encoding()} |
                      {includes, IncludePath :: [DirectoryName :: file:name()]} |
                      {source_name, SourceName :: file:name()} |
                      {macros, PredefMacros :: macros()} |
                      {name, FileName :: file:name()} |
                      {location, StartLocation :: erl_anno:location()} |
                      {fd, FileDescriptor :: file:io_device()} |
                      extra]
                 Epp = epp_handle()
                 Extra = [{encoding, source_encoding() | none}]
                 ErrorDescriptor = term()

              Opens a file for preprocessing.

              If you want  to  change  the  file  name  of  the  implicit  -file()  attributes  inserted  during
              preprocessing,  you can do with {source_name,SourceName}. If unset it will default to the name of
              the opened file.

              If extra is specified in Options, the return value is {ok,Epp,Extra} instead of {ok,Epp}.

              The option location is forwarded to the Erlang token scanner, see erl_scan:tokens/3,4.

       open(FileName,IncludePath)->
               {ok, Epp} | {error, ErrorDescriptor}

              Types:

                 FileName = file:name()
                 IncludePath = [DirectoryName :: file:name()]
                 Epp = epp_handle()
                 ErrorDescriptor = term()

              Equivalent to epp:open([{name,FileName},{includes,IncludePath}]).

       open(FileName,IncludePath,PredefMacros)->
               {ok, Epp} | {error, ErrorDescriptor}

              Types:

                 FileName = file:name()
                 IncludePath = [DirectoryName :: file:name()]
                 PredefMacros = macros()
                 Epp = epp_handle()
                 ErrorDescriptor = term()

              Equivalent to epp:open([{name,FileName},{includes,IncludePath},{macros,PredefMacros}]).

       parse_erl_form(Epp)->
                         {ok, AbsForm} |
                         {error, ErrorInfo} |
                         {warning, WarningInfo} |
                         {eof, Location}

              Types:

                 Epp = epp_handle()
                 AbsForm = erl_parse:abstract_form()
                 Location = erl_anno:location()
                 ErrorInfo = erl_scan:error_info() | erl_parse:error_info()
                 WarningInfo = warning_info()

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

       parse_file(FileName,Options)->
                     {ok, [Form]} |
                     {ok, [Form], Extra} |
                     {error, OpenError}

              Types:

                 FileName = file:name()
                 Options =
                     [{includes, IncludePath :: [DirectoryName :: file:name()]} |
                      {source_name, SourceName :: file:name()} |
                      {macros, PredefMacros :: macros()} |
                      {default_encoding, DefEncoding :: source_encoding()} |
                      {location, StartLocation :: erl_anno:location()} |
                      extra]
                 Form =
                     erl_parse:abstract_form() |
                     {error, ErrorInfo} |
                     {eof, Location}
                 Location = erl_anno:location()
                 ErrorInfo = erl_scan:error_info() | erl_parse:error_info()
                 Extra = [{encoding, source_encoding() | none}]
                 OpenError = file:posix() | badarg | system_limit

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

              If you want  to  change  the  file  name  of  the  implicit  -file()  attributes  inserted  during
              preprocessing,  you can do with {source_name,SourceName}. If unset it will default to the name of
              the opened file.

              If extra is specified in Options, the return value is {ok,[Form],Extra} instead of {ok,[Form]}.

              The option location is forwarded to the Erlang token scanner, see erl_scan:tokens/3,4.

       parse_file(FileName,IncludePath,PredefMacros)->
                     {ok, [Form]} | {error, OpenError}

              Types:

                 FileName = file:name()
                 IncludePath = [DirectoryName :: file:name()]
                 Form =
                     erl_parse:abstract_form() |
                     {error, ErrorInfo} |
                     {eof, Location}
                 PredefMacros = macros()
                 Location = erl_anno:location()
                 ErrorInfo = erl_scan:error_info() | erl_parse:error_info()
                 OpenError = file:posix() | badarg | system_limit

              Equivalent to epp:parse_file(FileName,[{includes,IncludePath},{macros,PredefMacros}]).

       read_encoding(FileName)->source_encoding()|noneread_encoding(FileName,Options)->source_encoding()|none

              Types:

                 FileName = file:name()
                 Options = [Option]
                 Option = {in_comment_only, boolean()}

              Read the encoding from a file. Returns the read encoding, or none if no valid encoding is found.

              Option in_comment_only is true by default, which is correct for Erlang source  files.  If  set  to
              false, the encoding string does not necessarily have to occur in a comment.

       read_encoding_from_binary(Binary)->source_encoding()|noneread_encoding_from_binary(Binary,Options)->
                                    source_encoding() | none

              Types:

                 Binary = binary()
                 Options = [Option]
                 Option = {in_comment_only, boolean()}

              Read the encoding from a binary. Returns the read encoding, or none if no valid encoding is found.

              Option  in_comment_only  is  true  by default, which is correct for Erlang source files. If set to
              false, the encoding string does not necessarily have to occur in a comment.

       scan_erl_form(Epp)->
                        {ok, Tokens} |
                        {error, ErrorInfo} |
                        {warning, WarningInfo} |
                        {eof, Line}

              Types:

                 Epp = epp_handle()
                 Tokens = erl_scan:tokens()
                 Line = erl_anno:line()
                 ErrorInfo = erl_scan:error_info() | erl_parse:error_info()
                 WarningInfo = warning_info()

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

       scan_file(FileName,Options)->
                    {ok, [Form], Extra} | {error, OpenError}

              Types:

                 FileName = file:name()
                 Options =
                     [{includes, IncludePath :: [DirectoryName :: file:name()]} |
                      {source_name, SourceName :: file:name()} |
                      {macros, PredefMacros :: macros()} |
                      {default_encoding, DefEncoding :: source_encoding()}]
                 Form = erl_scan:tokens() | {error, ErrorInfo} | {eof, Loc}
                 Loc = erl_anno:location()
                 ErrorInfo = erl_scan:error_info()
                 Extra = [{encoding, source_encoding() | none}]
                 OpenError = file:posix() | badarg | system_limit

              Preprocesses an Erlang source file returning a list of the lists  of  raw  tokens  of  each  form.
              Notice that the tuple {eof,Line} returned at the end of the file is included as a "form", and any
              failures to scan a form are included in the list as tuples {error,ErrorInfo}.

       set_encoding(File)->source_encoding()|none

              Types:

                 File = io:device()

              Reads  the  encoding  from  an  I/O  device  and  sets the encoding of the device accordingly. The
              position of the I/O device referenced by File is not affected. If no valid encoding  can  be  read
              from the I/O device, the encoding of the I/O device is set to the default encoding.

              Returns the read encoding, or none if no valid encoding is found.

       set_encoding(File,Default)->source_encoding()|none

              Types:

                 Default = source_encoding()
                 File = io:device()

              Reads  the  encoding  from  an  I/O  device  and  sets the encoding of the device accordingly. The
              position of the I/O device referenced by File is not affected. If no valid encoding  can  be  read
              from the I/O device, the encoding of the I/O device is set to the encoding specified by Default.

              Returns the read encoding, or none if no valid encoding is found.

       epp - An Erlang code preprocessor.

erl_parse(3erl)

Ericsson AB                                        stdlib 3.17                                         epp(3erl)