Re: How to get Incremental charecter groups in a string

[Jasper]

$_ = "this abc xyz abbc donut ghijkl";

"abcdefghijklmnopqrstuvwxyz" =~ $_ and print for split;

This approaches it from a slightly different angle, and removes the false positive 'abbc' results that you get from the $_ eq join sort split method...
You can add a /i in there if you wanted to ignore case.. :S

[GrandFather]

It's not clear that 'abbc' is a false positive, and it is not clear that skipping 'is' (as your code does) is appropriate. However the following fixes the supposed false positive and retains the possibly desired 'is':

use strict;
use warnings;

my $str="this is abc and bcf and xyz and ijklmn but not abbc";
my @words = split ' ', $str;
my @incWords = grep {
      my %uniq = map {$_ => 0} split ''; $_ eq join '', sort keys %uni
+q
  } @words;

print "@incWords";

Prints:

is abc bcf xyz ijklmn not

[Jasper]

Yes, well, yes, indeed, that does do what you say it does, but who knows what the OP wanted except the OP?

All I was showing was TMTOWTDI. Maybe. :)

[GrandFather]

I did like your trick of turning the regex inside out to check for incrementing runs of letters, but 'bcf' from OP's example argues against that being what is required. Nice trick though. :)

[ikegami]

Nice, but it would be faster to use index:

index('abcdefghijklmnopqrstuvwxyz', $_) >= 0 and print for split;