NAME

       PPI::Lexer - The PPI Lexer

SYNOPSIS

         use PPI;

         # Create a new Lexer
         my $Lexer = PPI::Lexer->new;

         # Build a PPI::Document object from a Token stream
         my $Tokenizer = PPI::Tokenizer->load('My/Module.pm');
         my $Document = $Lexer->lex_tokenizer($Tokenizer);

         # Build a PPI::Document object for some raw source
         my $source = "print 'Hello World!'; kill(Humans->all);";
         $Document = $Lexer->lex_source($source);

         # Build a PPI::Document object for a particular file name
         $Document = $Lexer->lex_file('My/Module.pm');

DESCRIPTION

       The is the PPI Lexer. In the larger scheme of things, its job is to take token streams, in
       a variety of forms, and "lex" them into nested structures.

       Pretty much everything in this module happens behind the scenes at this point. In fact, at
       the moment you don't really need to instantiate the lexer at all, the three main methods
       will auto-instantiate themselves a "PPI::Lexer" object as needed.

       All methods do a one-shot "lex this and give me a PPI::Document object".

       In fact, if you are reading this, what you probably want to do is to just "load a
       document", in which case you can do this in a much more direct and concise manner with one
       of the following.

         use PPI;

         $Document = PPI::Document->load( $filename );
         $Document = PPI::Document->new( $string );

       See PPI::Document for more details.

       For more unusual tasks, by all means forge onwards.

METHODS

   new
       The "new" constructor creates a new "PPI::Lexer" object. The object itself is merely used
       to hold various buffers and state data during the lexing process, and holds no significant
       data between ->lex_xxxxx calls.

       Returns a new "PPI::Lexer" object

   lex_file $filename
       The "lex_file" method takes a filename as argument. It then loads the file, creates a
       PPI::Tokenizer for the content and lexes the token stream produced by the tokenizer.
       Basically, a sort of all-in-one method for getting a PPI::Document object from a file
       name.

       Returns a PPI::Document object, or "undef" on error.

   lex_source $string
       The "lex_source" method takes a normal scalar string as argument. It creates a
       PPI::Tokenizer object for the string, and then lexes the resulting token stream.

       Returns a PPI::Document object, or "undef" on error.

   lex_tokenizer $Tokenizer
       The "lex_tokenizer" takes as argument a PPI::Tokenizer object. It lexes the token stream
       from the tokenizer into a PPI::Document object.

       Returns a PPI::Document object, or "undef" on error.

   errstr
       For any error that occurs, you can use the "errstr", as either a static or object method,
       to access the error message.

       If no error occurs for any particular action, "errstr" will return false.

TO DO

       - Add optional support for some of the more common source filters

       - Some additional checks for blessing things into various Statement and Structure
       subclasses.

SUPPORT

       See the support section in the main module.

AUTHOR

       Adam Kennedy <adamk@cpan.org>

COPYRIGHT

       Copyright 2001 - 2011 Adam Kennedy.

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.

       The full text of the license can be found in the LICENSE file included with this module.