> These are fields that will/won't be sent from front end. My code for each of these fields is in separate if(@arr_0), if($scal_1) blocks. So if any of these variables don't exist, the related code will not execute.

This is a misconception, a variable must already exist to be tested the way you do (at least under use strict ) , but it can hold a false value if you wanna disable the block.

It looks like all var-names are known beforehand, otherwise you wouldn't be able to write code testing it!

hence you are free to write

our @arr_0  = @{ $hash{arr_0} // [] } ;
our $scal_1 = $hash{scal_1} ;

[download]

both will be false if missing.

BTW use exists not defined to test hash elements.

still a very weird requirement, about how many variables are we talking?

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re^3: How to create variables for each hash key that has a value. by LanX
in thread How to create variables for each hash key that has a value. by Perl300

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