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.