1PPI::Statement(3)     User Contributed Perl Documentation    PPI::Statement(3)
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NAME

6       PPI::Statement - The base class for Perl statements
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INHERITANCE

9         PPI::Statement
10         isa PPI::Node
11             isa PPI::Element
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DESCRIPTION

14       PPI::Statement is the root class for all Perl statements. This includes
15       (from perlsyn) "Declarations", "Simple Statements" and "Compound State‐
16       ments".
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18       The class PPI::Statement itself represents a "Simple Statement" as
19       defined in the perlsyn manpage.
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STATEMENT CLASSES

22       Please note that unless documented themselves, these classes are yet to
23       be frozen/finalised. Names may change slightly or be added or removed.
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25       PPI::Statement::Scheduled
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27       This covers all "scheduled" blocks, chunks of code that are executed
28       separately from the main body of the code, at a particular time. This
29       includes all "BEGIN", "CHECK", "INIT" and "END" blocks.
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31       PPI::Statement::Package
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33       A package declaration, as defined in perlfunc.
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35       PPI::Statement::Include
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37       A statement that loads or unloads another module.
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39       This includes 'use', 'no', and 'require' statements.
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41       PPI::Statement::Sub
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43       A named subroutine declaration, or forward declaration
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45       PPI::Statement::Variable
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47       A variable declaration statement. This could be either a straight dec‐
48       laration or also be an expression.
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50       This includes all 'my', 'local' and 'out' statements.
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52       PPI::Statement::Compound
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54       This covers the whole family of 'compound' statements, as described in
55       perlsyn.
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57       This includes all statements starting with 'if', 'unless', 'for',
58       'foreach' and 'while'. Note that this does NOT include 'do', as it is
59       treated differently.
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61       All compound statements have implicit ends. That is, they do not end
62       with a ';' statement terminator.
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64       PPI::Statement::Break
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66       A statement that breaks out of a structure.
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68       This includes all of 'redo', 'next', 'last' and 'return' statements.
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70       PPI::Statement::Data
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72       A special statement which encompasses an entire "__DATA__" block,
73       including the initial '__DATA__' token itself and the entire contents.
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75       PPI::Statement::End
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77       A special statement which encompasses an entire __END__ block, includ‐
78       ing the initial '__END__' token itself and the entire contents, includ‐
79       ing any parsed PPI::Token::POD that may occur in it.
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81       PPI::Statement::Expression
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83       PPI::Statement::Expression is a little more speculative, and is
84       intended to help represent the special rules relating to "expressions"
85       such as in:
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87         # Several examples of expression statements
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89         # Boolean conditions
90         if ( expression ) { ... }
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92         # Lists, such as for arguments
93         Foo->bar( expression )
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95       PPI::Statement::Null
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97       A null statement is a special case for where we encounter two consecu‐
98       tive statement terminators. ( ;; )
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100       The second terminator is given an entire statement of its own, but one
101       that serves no purpose. Hence a 'null' statement.
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103       Theoretically, assuming a correct parsing of a perl file, all null
104       statements are superfluous and should be able to be removed without
105       damage to the file.
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107       But don't do that, in case PPI has parsed something wrong.
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109       PPI::Statement::UnmatchedBrace
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111       Because PPI is intended for use when parsing incorrect or incomplete
112       code, the problem arises of what to do with a stray closing brace.
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114       Rather than die, it is allocated its own "unmatched brace" statement,
115       which really means "unmatched closing brace". An unmatched open brace
116       at the end of a file would become a structure with no contents and no
117       closing brace.
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119       If the document loaded is intended to be correct and valid, finding a
120       PPI::Statement::UnmatchedBrace in the PDOM is generally indicative of a
121       misparse.
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123       PPI::Statement::Unknown
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125       This is used temporarily mid-parsing to hold statements for which the
126       lexer cannot yet determine what class it should be, usually because
127       there are insufficient clues, or it might be more than one thing.
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129       You should never encounter these in a fully parsed PDOM tree.
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METHODS

132       "PPI::Statement" itself has very few methods. Most of the time, you
133       will be working with the more generic PPI::Element or PPI::Node meth‐
134       ods, or one of the methods that are subclass-specific.
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136       label
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138       One factor common to most statements is their ability to be labeled.
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140       The "label" method returns the label for a statement, if one has been
141       defined, but without the trailing colon. Take the following example
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143         MYLABEL: while ( 1 .. 10 ) { last MYLABEL if $_ > 5 }
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145       For the above statement, the "label" method would return 'MYLABEL'.
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147       Returns false if the statement does not have a label.
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149       stable
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151       Much like the PPI::Document method of the same name, the ->stable
152       method converts a statement to source and back again, to determine if a
153       modified statement is still legal, and won't be interpreted in a dif‐
154       ferent way.
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156       Returns true if the statement is stable, false if not, or "undef" on
157       error.
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TO DO

160       - Complete, freeze and document the remaining classes
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SUPPORT

163       See the support section in the main module.
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AUTHOR

166       Adam Kennedy <adamk@cpan.org>
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169       Copyright 2001 - 2006 Adam Kennedy.
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171       This program is free software; you can redistribute it and/or modify it
172       under the same terms as Perl itself.
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174       The full text of the license can be found in the LICENSE file included
175       with this module.
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179perl v5.8.8                       2006-09-23                 PPI::Statement(3)
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