in reply to variable inside hash key

One way... 
use warnings;
use strict;

my $pic = 1;
my $v = {R3R3_1_IF => 555};
my $key = "R3R3_${pic}_IF";
print "set groups interfaces $v->{$key}\n";

__END__

set groups interfaces 555

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Re^2: variable inside hash key
by Anonymous Monk on Mar 30, 2016 at 01:12 UTC

    Thank you, toolic. It worked

[reply]
Re^2: variable inside hash key
by Anonymous Monk on Apr 06, 2016 at 05:55 UTC

    I think increment of $pic is not happening with this method 

     

my $pic = 1;
my $key_MS = "R3R3_${pic}_IF";
my $temp = 90;

          for (my $ip = 1; $ip<=100; $ip++) {
             if ($temp == $ip) {
             $pic++;
            }
        }
        print "New pic value is $key_MS\n";


output:New pic value is R3R3_1_IF

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[d/l]

      $pic is being incremented. This however has absolutely no effect on $key_MS which was set and evaluated when $pic was still 1. If you want to have it re-evaluated every time it is referenced you would need a closure or an eval or similar. eg. (with the loop replaced for clarity)

      #!/usr/bin/env perl 
use strict;
use warnings;

my $pic = 1;
my $key_MS = sub { "R3R3_${pic}_IF"; };
print "Old pic value is " . &$key_MS . "\n";
$pic = 2;
print "New pic value is " . &$key_MS . "\n";

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[reply]
[d/l]
[select]

        The problem with this is, i need to use the output &$key_MS, with in a hash key and it may not work 

        
my $key_MS = sub { "R3R3_${pic}_IF"; };

print "set service-interface $v->{&$key_MS}.0\n";

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[d/l]

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