Perl range

drake50 has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: Perl range by FunkyMonk (Bishop) on Oct 03, 2007 at 19:23 UTC
`perl -e 'foreach $index (reverse( 5..9 ), 12..18) { print "$index\n" } +' #update: or perl -e 'print "$_\n" for reverse( 5..9 ), 12..18'` [download]	[reply] [d/l] [select]
Re^2: Perl range by drake50 (Pilgrim) on Oct 03, 2007 at 19:49 UTC
Nice. I don't know why I didn't think of reverse!	[reply]
Re^3: Perl range by naikonta (Curate) on Oct 04, 2007 at 16:55 UTC
That explains your short node title. If you thought, "hey I want the reverse version of the range...", you might have put a title such "Reversing Perl range". In this case, there was a great chance that you would resolve it yourself without firing a node. The good side is you generated a pretty high attention and resulted in a pretty interesting thread :-) Update: I would FP this myself. Open source softwares? Share and enjoy. Make profit from them if you can. Yet, share and enjoy!	[reply]
Re: Perl range by johngg (Canon) on Oct 03, 2007 at 20:29 UTC
You can also use the `-l` switch to automatically append a line terminator for each `print` operation, thus allowing `print` to output `$_` by default. `perl -le 'print for reverse(5 .. 9), 12 .. 18;'` [download] I hope this is of use. Cheers, JohnGG	[reply] [d/l] [select]
Re: Perl range by mwah (Hermit) on Oct 03, 2007 at 19:55 UTC
another one: `perl -e 'print abs,"\n" for -9..-5, 12..18'` [download] mwa	[reply] [d/l]
Re^2: Perl range by Firefly258 (Beadle) on Oct 06, 2007 at 04:44 UTC
`perl -le 'for $i (map abs, -9..-5, 1..3) { print $i }'` `perl -e '$,=$",$_=(split/\W/,$^X)[y[eval]]]+--$_],print+just,another,split,hack'er`	[reply] [d/l] [select]
Re: Perl range by ikegami (Patriarch) on Oct 03, 2007 at 20:09 UTC
And a generic solution: `for ([9,5], [12,18]) { my ($i, $j) = @$_; my $f = ($i <= $j ? 1 : -1); for ($f$i .. $f$j) { my $index = $f*$_; print("$index\n"); } }` [download]	[reply] [d/l]