hi monks,

quick and easy one, i hope. i want to use the matching metacharacter '{}' to match a number of instances of a character, but i want to calculate that number "on the fly" (vs hard-coding a number, or creating a variable just for that regex). i'm not sure if i can do this, but here's what i tried, which fails: 

#!/usr/bin/perl
use strict;
use warnings;
my $foo = shift || 12;
my $i = 1;
print "Is \`$foo' a two-digit number ... ";
my $rc = ($foo =~ /^[0-9]{($i + 1)}$/) ? 'yes' : 'no';
#my $rc = ($foo =~ /^[0-9]{2}$/) ? 'yes' : 'no';
print $rc,"\n";

[download]
if i use the commented out code, it works. it is no biggie if i have to create the variable first, but it just feels like there ought to be a way to do this.

btw, i know there are betters ways to check for a two-digit number, this is just a simplified example of my problem.

thanks.

In reply to Calculating variable {n} in regex match by atreyu

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