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Top Forums Shell Programming and Scripting Perl syntax that I don't understand. Post 302522197 by mirni on Friday 13th of May 2011 04:11:59 PM
Old 05-13-2011
@bartus: but he's assigning it into a scalar:
Code:
$somescalar = [['one','two'],['three','four']];

So he'll end up with $somescalar being a reference to an anonymous array.

@mrwatkin:
You are right. The first construct will create a reference to an array. You can access the array elements through -> operator, like
Code:
$el11 = $somescalar->[1][1];   #el11 == "four"
$el11 = $myarray[1][1];  #el11 == "four"

Except the array is initialized straight there, instead of doing:
Code:
@myarray = (['one','two'],['three','four']);
$somescalar = \@myarray;

The advantage of working with references is that when you are passing them through a function, you are just passing an address to memory, instead of copying the whole thing over (passing by value).

BTW, in defining the @myarray you are using the anonymous array construct also: ['one','two'] will yield a reference to an array containing 'one' and 'two'.
 

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PPIx::Regexp::Token::GroupType::Code(3pm)		User Contributed Perl Documentation		 PPIx::Regexp::Token::GroupType::Code(3pm)

NAME
PPIx::Regexp::Token::GroupType::Code - Represent one of the embedded code indicators SYNOPSIS
use PPIx::Regexp::Dumper; PPIx::Regexp::Dumper->new( 'qr{(?{print "hello world! ")}smx' ) ->print(); INHERITANCE
"PPIx::Regexp::Token::GroupType::Code" is a PPIx::Regexp::Token::GroupType. "PPIx::Regexp::Token::GroupType::Code" has no descendants. DESCRIPTION
This method represents one of the embedded code indicators, either '?' or '??', in the zero-width assertion (?{ print "Hello, world! " }) or the old-style deferred expression syntax my $foo; $foo = qr{ foo (??{ $foo }) }smx; METHODS
This class provides no public methods beyond those provided by its superclass. SUPPORT
Support is by the author. Please file bug reports at <http://rt.cpan.org>, or in electronic mail to the author. AUTHOR
Thomas R. Wyant, III wyant at cpan dot org COPYRIGHT AND LICENSE
Copyright (C) 2009-2012 by Thomas R. Wyant, III This program is free software; you can redistribute it and/or modify it under the same terms as Perl 5.10.0. For more details, see the full text of the licenses in the directory LICENSES. This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. perl v5.14.2 2012-06-06 PPIx::Regexp::Token::GroupType::Code(3pm)
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