Hi, I have a string ($sentence) containing pattern in this format:

A~~~.*~A

Now I wanna extract all "A~~~.*~A" from the string, each time i find one match, I change the $_ to contain the rest of the string, then sub the string by s/$_// and assign to $remainPart, so that the $remainPart only store the portion before this "A~~~.*~A" pattern..

However, i have a problem here, i extract $_ from $sentence, but cannot use it to sub $remainPart(which is equal to $sentence originally). Wondering why. Any suggestion?

Here is the source code:

#! usr/bin/perl
      $sentence = " he PP
             study VB
             A~~~language~A NP
             and CC
             play VB
             A~~~game~A NP
             ."
      $_ = $sentence;
      while ($_ ne '') {
           if  (m/A~~~(.*)~A/g) {   # global match
                $remainPart = $sentence;
                ($_) = /(\G(.|\n)*)/g;  # store rest of the string
                                        # (after pos) to $_   
                $remainPart =~ s/$_//;
                print "$remainPart\n";
           } else {
                $_ = '';
           }
      }

[download]

By right, first time the $_ will contain 

" NP
and CC
play VB
A~~~game~A NP
."

[download]

but as the $remainPart is printed out, it is still same as $sentence, which indicates the substitution is not successful.

In reply to Regexp Substitution Problem!! by bmal

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