1PPI::Token::Prototype(3U)ser Contributed Perl DocumentatiPoPnI::Token::Prototype(3)
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6 PPI::Token::Prototype - A subroutine prototype descriptor
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9 PPI::Token::End
10 isa PPI::Token
11 isa PPI::Element
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14 sub ($@) prototype;
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17 Although it sort of looks like a list or condition, a subroutine
18 prototype is a lot more like a string. Its job is to provide hints to
19 the perl compiler on what type of arguments a particular subroutine
20 expects, which the compiler uses to validate parameters at compile-
21 time, and allows programmers to use the functions without explicit
22 parameter parens.
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24 Due to the rise of OO Perl coding, which ignores these prototypes, they
25 are most often used to allow for constant-like things, and to "extend"
26 the language and create things that act like keywords and core
27 functions.
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29 # Create something that acts like a constant
30 sub MYCONSTANT () { 10 }
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32 # Create the "any" core-looking function
33 sub any (&@) { ... }
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35 if ( any { $_->cute } @babies ) {
36 ...
37 }
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40 This class provides one additional method beyond those defined by the
41 PPI::Token and PPI::Element parent classes.
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43 prototype
44 The "prototype" accessor returns the actual prototype pattern, stripped
45 of flanking parens and of all whitespace. This mirrors the behavior of
46 the Perl "prototype" builtin function.
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48 Note that stripping parens and whitespace means that the return of
49 "prototype" can be an empty string.
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52 See the support section in the main module.
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55 Adam Kennedy <adamk@cpan.org>
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58 Copyright 2001 - 2011 Adam Kennedy.
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60 This program is free software; you can redistribute it and/or modify it
61 under the same terms as Perl itself.
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63 The full text of the license can be found in the LICENSE file included
64 with this module.
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68perl v5.28.1 2017-06-22 PPI::Token::Prototype(3)