Keyboard shortcuts

Press or to navigate between chapters

Press S or / to search in the book

Press ? to show this help

Press Esc to hide this help

Use map to filter and enrich

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

my @numbers = (1..5);

my @riches = map { $_ > 3 ? ($_+1, $_+2) : () } @numbers;
print "@riches\n"; # 5 6 6 7