We help IT Professionals succeed at work.

Pattern matching

leoleo asked
Last Modified: 2012-05-04


 I have a variable like this,
$var_name = "AA first BB second AA third BB fourth AA 5th BB";
I want to read the characters between 'AA' and 'BB' ie., (first, third, 5th).

[The number of AA-BB combinations is not defined.]

How do I do this?
Watch Question

$var_name = "AA first BB second AA third BB fourth AA 5th BB";
@Bits = split /AA|BB/, $var_name;
foreach $Chunk (@Bits) {
   print "$Chunk\n";
$var_name = "AA first BB second AA third BB fourth AA 5th BB";
@Bits = split /AA|BB/, $var_name;
foreach $Chunk (@Bits) {
   print "$Chunk\n";
Hey, it got posted twice (and its not perfect).

I have now reread the question, and here is the right answer:

$var_name = "AA first BB second AA third BB fourth AA 5th BB";
@Bits = split /BB/, $var_name;
foreach $Chunk (@Bits) {
   ($Bad, $Good) = split /AA/, $Chunk;
   print "$Good\n";
This one is on us!
(Get your first solution completely free - no credit card required)
Cunning, mrachow



Thanks, PC_User321 & mrachow. Both the solns worked.

@ the very least, I would use /\bAA\b/ and /\bBB\b/ as splitters. These will work assuming your fields do not contain AA or BB isolated by non word characters.

The proposed solution does not work on, for instance:


OTOH, if a separator can be a valid field value, no amount of regexp will do, and you have to resort to more detailed parsing.



Gain unlimited access to on-demand training courses with an Experts Exchange subscription.

Get Access
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Empower Your Career
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE

Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Unlock the solution to this question.
Join our community and discover your potential

Experts Exchange is the only place where you can interact directly with leading experts in the technology field. Become a member today and access the collective knowledge of thousands of technology experts.

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.