The keyboard input is captured on STDIN:

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

my $input;
print("Your number: "), chomp( $input = <STDIN> )
    until $input =~ /^\d+$/;
print 3 * $input - 1, $/;

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The print, chomp sequence uses the comma operator to make the two part of a single expression for the modifier. The alternative is do { print... ; chomp ...;} until ...;.

After Compline,
Zaxo

In reply to Re: Input/Output through the Keyboard by Zaxo
in thread Input/Output through the Keyboard by @rocks

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