how do I use Posix isdigit function?

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Re: how do I use Posix isdigit function?
by japhy (Canon) on May 09, 2002 at 06:06 UTC

use POSIX 'isdigit';
if (isdigit($c)) { print "$c is a digit" }
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$c =~ /\A\d\z/

length($c) == 1 and ord($c) >= ord(0) and ord($c) <= ord(9)

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Re: how do I use Posix isdigit function?
by Zaxo (Archbishop) on May 09, 2002 at 06:22 UTC

For the mechanics of calling POSIX functions, you can keep the overhead down by only importing the names you want to use:

#!/usr/bin/perl
use warnings;
use strict;

use POSIX qw( isdigit );
for (<DATA>) {
    print $_,
          isdigit($_) ? ' is' : ' is not';
          ' all digits.',
          $/;
}
__DATA__    
7
5
A
75A
433
12340
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/\d/

/^\d+$/

After Compline,
Zaxo

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Re: how do I use Posix isdigit function?
by grep (Monsignor) on May 09, 2002 at 06:05 UTC

m/\d/

A regex is much more idiomatic and you can save the overhead of the POSIX module

UPDATE: From the docs
This is identical to the C function, except that it can apply to a single character or to a whole string. Consider using regular expressions and the /[[:isdigit:]]/ construct instead, or the /\d/ construct

grep

Unix - where you can throw the manual on the keyboard and get a command

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