I'm not sure if I've understood your requirement as I can't tell where the 'g' comes from in your output. However, this should get rid of any 'X_' occurances after a '__'.

use strict;
use warnings;

my @strings = qw{
   KHI0339B__P_H_Vita_Korangi_Ind_A
   HGW6120A__S_Popalzai_Cross_A
   };

my $rxPatt = qr{(?<=__)[A-Z]_};
foreach my $string ( @strings )
{
    print qq{Original: $string\n};
    $string =~ s{$rxPatt}{}
       while $string =~ $rxPatt;
    print qq{Modified: $string\n\n};
}

[download]

The output is

Original: KHI0339B__P_H_Vita_Korangi_Ind_A
Modified: KHI0339B__Vita_Korangi_Ind_A

Original: HGW6120A__S_Popalzai_Cross_A
Modified: HGW6120A__Popalzai_Cross_A

[download]

I hope this is of use.

Cheers,

JohnGG

In reply to Re: question : regex by johngg
in thread question : regex by greatshots

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