1PPI::Lexer(3) User Contributed Perl Documentation PPI::Lexer(3)
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6 PPI::Lexer - The PPI Lexer
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9 use PPI;
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11 # Create a new Lexer
12 my $Lexer = PPI::Lexer->new;
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14 # Build a PPI::Document object from a Token stream
15 my $Tokenizer = PPI::Tokenizer->load( 'My/Module.pm' );
16 my $Document = $Lexer->lex_tokenizer( $Tokenizer );
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18 # Build a PPI::Document object for some raw source
19 my $source = "print 'Hello World!'; kill(Humans->all);";
20 $Document = $Lexer->lex_source( $source );
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22 # Build a PPI::Document object for a particular file name
23 $Document = $Lexer->lex_file( 'My/Module.pm' );
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26 The is the PPI Lexer. In the larger scheme of things, its job is to
27 take token streams, in a variety of forms, and "lex" them into nested
28 structures.
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30 Pretty much everything in this module happens behind the scenes at this
31 point. In fact, at the moment you don't really need to instantiate the
32 lexer at all, the three main methods will auto-instantiate themselves a
33 "PPI::Lexer" object as needed.
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35 All methods do a one-shot "lex this and give me a PPI::Document
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38 In fact, if you are reading this, what you probably want to do is to
39 just "load a document", in which case you can do this in a much more
40 direct and concise manner with one of the following.
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42 use PPI;
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44 $Document = PPI::Document->load( $filename );
45 $Document = PPI::Document->new( $string );
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47 See PPI::Document for more details.
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49 For more unusual tasks, by all means forge onwards.
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52 new
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54 The "new" constructor creates a new "PPI::Lexer" object. The object
55 itself is merely used to hold various buffers and state data during the
56 lexing process, and holds no significant data between ->lex_xxxxx
57 calls.
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59 Returns a new "PPI::Lexer" object
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61 lex_file $filename
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63 The "lex_file" method takes a filename as argument. It then loads the
64 file, creates a PPI::Tokenizer for the content and lexes the token
65 stream produced by the tokenizer. Basically, a sort of all-in-one
66 method for getting a PPI::Document object from a file name.
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68 Returns a PPI::Document object, or "undef" on error.
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70 lex_source $string
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72 The "lex_source" method takes a normal scalar string as argument. It
73 creates a PPI::Tokenizer object for the string, and then lexes the
74 resulting token stream.
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76 Returns a PPI::Document object, or "undef" on error.
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78 lex_tokenizer $Tokenizer
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80 The "lex_tokenizer" takes as argument a PPI::Tokenizer object. It lexes
81 the token stream from the tokenizer into a PPI::Document object.
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83 Returns a PPI::Document object, or "undef" on error.
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85 errstr
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87 For any error that occurs, you can use the "errstr", as either a static
88 or object method, to access the error message.
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90 If no error occurs for any particular action, "errstr" will return
91 false.
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94 - Add optional support for some of the more common source filters
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96 - Some additional checks for blessing things into various Statement and
97 Structure subclasses.
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100 See the support section in the main module.
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103 Adam Kennedy <adamk@cpan.org>
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106 Copyright 2001 - 2006 Adam Kennedy.
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108 This program is free software; you can redistribute it and/or modify it
109 under the same terms as Perl itself.
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111 The full text of the license can be found in the LICENSE file included
112 with this module.
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116perl v5.8.8 2006-09-23 PPI::Lexer(3)