PPI::Token::Prototype - A subroutine prototype descriptor
PPI::Token::End
isa PPI::Token
isa PPI::Element
sub ($@) prototype;
Although it sort of looks like a list or condition, a subroutine
prototype is a lot more like a string. Its job is to provide hints
to the perl compiler on what type of arguments a particular subroutine
expects, which the compiler uses to validate parameters at compile-time,
and allows programmers to use the functions without explicit parameter
parens.
Due to the rise of OO Perl coding, which ignores these prototypes, they
are most often used to allow for constant-like things, and to ``extend''
the language and create things that act like keywords and core functions.
# Create something that acts like a constant
sub MYCONSTANT () { 10 }
# Create the "any" core-looking function
sub any (&@) { ... }
if ( any { $_->cute } @babies ) {
...
}
This class provides one additional method beyond those defined by the
the PPI::Token manpage and the PPI::Element manpage parent classes.
The prototype accessor returns the actual prototype pattern, stripped
of flanking parens and of all whitespace. This mirrors the behavior of
the Perl prototype builtin function.
Note that stripping parens and whitespace means that the return of
prototype can be an empty string.
See the support section in the main module.
Adam Kennedy <adamk@cpan.org>
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.
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