in reply to undef/defined &{$name} while "strict refs"

You could use "the one exception to the rule": 
#!/usr/bin/perl -l

use autodie;
use common::sense;

sub walk {
    use strict qw/refs/;
    use warnings FATAL => 'syntax';
    print "Walk this!";
}

sub run {
    use strict qw/refs/;
    use warnings FATAL => 'syntax';
    print "Run with this!";
}

my $walkable = defined &{ 'walk' };
undef &{'walk'};
my $runable  = \&{ 'run' };
&$runable;

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Re^2: undef/defined &{$name} while "strict refs"
by anazawa (Scribe) on Aug 21, 2012 at 03:22 UTC
    Thanks to your explanation, I understand "strict refs" allows the following: 
    my $runable = \&{ 'run' };
&$runable;

    [download]
    Your code shows how we avoid throwing exceptions. I think, however, it's still unclear why defined/undef &{ 'run' } doesn't throw exceptions while "strict refs".
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      I think, however, it's still unclear why defined/undef &{ 'run' } doesn't throw exceptions while "strict refs". ,/i>

      Have you read what strict says about refs?

      Please read it now

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        The POD says we are allowed to get a reference to CODE using symbolic references while "strict refs". I think this doesn't mean we can defined or undef subroutines as well. I may be misreading the document.
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