The ternary operator exists in many programming languages and is often a stumbling block for many who encounter it for the first time. I'm sure I scratched my head over it too. Here's an example of usage: 

use strict;
use warnings;

my %hash = ( abc => 123 );

my $abc = exists $hash{abc} ? $hash{abc} : 0;

my $xyz = exists $hash{xyz} ? $hash{xyz} : 0;

print "ABC = $abc : XYZ = $xyz\n";

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This outputs: 

ABC = 123 : XYZ = 0

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Another thing you need to know is that variables declared with my are lexical. With your example code, this means the first $vxdgs only exists in the if block and the second $vxdgs only exists in the else block; furthermore, they are two completely separate variables with their own values.

From your question, I believe the code you want is: 

my $vxdg = exists $vxdgs{$node}{$disk} ? $vxdgs{$node}{$disk} : "";

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-- Ken

In reply to Re: Short form (ternary) if else by kcott
in thread Short form (ternary) if else by gg48gg

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