Re^4: How to pass a variable string as conditional argument to if statment

Hi, I have a variable $var = '10>5"; This string is obtained from a table and is stored in the variable. I want to evaluate this string. If it is true, then execute. E.g, if($var is true){ }else { } I tried to use eval but is not working as expected.

Comment on Re^4: How to pass a variable string as conditional argument to if statment

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Re^5: How to pass a variable string as conditional argument to if statment by poj (Abbot) on Feb 06, 2016 at 07:00 UTC
Are you checking for errors after the eval ? `#!perl use strict; my @test = ('10>5','10<5','13+2==14+1','4>(6/2)+1'); for my $var (@test){ my $result = eval $var ? 'True' : 'False'; die $@ if $@; # check for errors in eval print "$var is $result\n"; }` [download] poj	[reply] [d/l]
Re^5: How to pass a variable string as conditional argument to if statment by choroba (Cardinal) on Feb 06, 2016 at 08:25 UTC
You should validate the string before running eval on it. Imagine the string contains `system 'rm -rf /'` [download] or something similar. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]