use strict;
use warnings;

my %colors = (
    blue => "#0000ff",
    red => "#ff0000",
    green => "#00ff00",
);

{
    no strict;

    while (my ($color, $color_code) = each(%colors)) {
        *$color = sub {
            "<font color=\"$color_code\">@_</font>";
        };
    }
}

print red("Hello"), "\n";
print green("World"), "\n";