loop over a string to do search/replacement using regexp?

[Rick]

Hi, guys

I need to loop over a string to find some pattern A, do some
computation according to A and replace A with B. I am trying to do this
within a while loop but I have no idea how to plug s///g into this
loop. Can anyone offer some clue?

Here is an example: In string 'a123ba456b', the pattern to find is
a(.*?)b and this string needs to be processed as 'a(1)ba(2)b', meaning
that the occurance of '123' is recorded and put back into the original
string.

Thanks a million!

Rick

 

[Gunnar Hjalmarsson]

I need to loop over a string to find some pattern A, do some
computation according to A and replace A with B. I am trying to do this
within a while loop but I have no idea how to plug s///g into this
loop. Can anyone offer some clue?

Here is an example: In string 'a123ba456b', the pattern to find is
a(.*?)b and this string needs to be processed as 'a(1)ba(2)b', meaning
that the occurance of '123' is recorded and put back into the original
string.

my $string = 'a123ba456b';
my (%vars, $i);
( my $newstring = $string ) =~ s{a(.*?)b}{
$vars{ ++$i } = $1;
"a($i)b";
}eg;