sub natural_sort {
    return @_ if @_ < 2;
    my $index = 0;
    return @_[@_».lc».subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g).map( *~' '~$index++ ).sort.map({@(split(' ',$^_))[*-1]})];
}

##</code><code>##

sub natural_cmp ($a, $b) {
   return [leg] ($a, $b)».lc».subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g);
}

##</code><code>##

my %cache;
sub cached_natural_cmp ($a, $b) {
    return [leg] ($a, $b)».lc.map( %cache{ * } //= *.subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g));
}

##</code><code>##

 @array.sort(*.lc.subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g));

##</code><code>##

@array.sort: natural(*);
   
sub natural ($) { *.lc.subst(/(\d+)/, -> $/{ sprintf( "%s%c%s", 0, $0.chars, $0) }, :g) }

##</code><code>##

.say for %words.keys.sort: natural(*);

or 

%words.keys.sort( natural(*) )».say;