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Full Discussion: perl: eval and constants
Top Forums Shell Programming and Scripting perl: eval and constants Post 60653 by zazzybob on Thursday 20th of January 2005 05:48:39 AM
Old 01-20-2005
Do you mean something like this?

Code:
#!/usr/bin/perl

@foo=('FOOD','NUMBER','OS');
@bar=('pizza','two','unix');

foreach $foo_val ( @foo ) {
  eval "\$$foo_val = @bar[$count]";
  ++$count;
}
print "\$FOOD IS $FOOD\n";
print "\$NUMBER IS $NUMBER\n";
print "\$OS IS $OS\n";

Cheers
ZB
 

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Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEUser3Contributed Perl DocumePerl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval(3)

NAME
Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval - Write "eval { my $foo; bar($foo) }" instead of "eval "my $foo; bar($foo);"". AFFILIATION
This Policy is part of the core Perl::Critic distribution. DESCRIPTION
The string form of "eval" is recompiled every time it is executed, whereas the block form is only compiled once. Also, the string form doesn't give compile-time warnings. eval "print $foo"; # not ok eval {print $foo}; # ok CONFIGURATION
There is an "allow_includes" boolean option for this Policy. If set, then strings that look like they only include a single "use" or "require" statement (with the possible following statement that consists of a single number) are allowed. With this option set, the following are flagged as indicated: eval 'use Foo'; # ok eval 'require Foo'; # ok eval "use $thingy;"; # ok eval "require $thingy;"; # ok eval "use $thingy; 1;"; # ok eval "require $thingy; 1;"; # ok eval 'use Foo; blah;'; # still not ok eval 'require Foo; 2; 1;'; # still not ok eval 'use $thingy;'; # still not ok eval 'no Foo'; # still not ok If you don't understand why the number is allowed, see Perl::Critic::Policy::ErrorHandling::RequireCheckingReturnValueOfEval. This option inspired by Ricardo SIGNES' Perl::Critic::Policy::Lax::ProhibitStringyEval::ExceptForRequire. SEE ALSO
Perl::Critic::Policy::ControlStrucutres::RequireBlockGrep Perl::Critic::Policy::ControlStrucutres::RequireBlockMap AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com> COPYRIGHT
Copyright (c) 2005-2011 Imaginative Software Systems. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license can be found in the LICENSE file included with this module. perl v5.16.3 2014-06-09 Perl::Critic::Policy::BuiltinFunctions::ProhibitStringyEval(3)
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