Dear Monks

in my perl script, I am running few commands which result 0 or < 0 which will be later used for an arithmetic calculation.

but in some cases command may throw error and arithmetic calculation may give an result which is not expected.

so I would like to validate if return output from command is numeric or not.

I see many people recommended if section in below code.


use warnings;
my $cmd = "cmd";
my $value = qx($cmd);

my $cmd1 = "cmd1";
my $value1 = qx($cmd1);

if (($value+0) eq $value) {
print $value . " is numeric";
}
else
{
print $value . " is not numeric";
}

if (($value1+0) eq $value1) {
print $value1 . " is numeric";
}
else
{
print $value1 . " is not numeric";
}

my $total = $value + $value1;
print $total;   // this gives me total of two values.

[download]

I tried to use the same but always result is not numeric which it could be but then i would expect warning while performing the arithmetic operation but i get correct result there so i believe $value is numeric but validation code has some problem.

any pointers?

In reply to validate if output of command is numeric or not by kaka_2

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