I believe that I need to include executable Perl code in the regex to reduce the match position variable after each matching string. Then ALL substrings of format _[^']+?_ should be matched: 
#! /usr/bin/perl -w

use strict;
use locale;

my $string1 = "_'nada_komo_el_'sol_";
my $string2 = "_na'da_komo_el_so'l_";

$string1 =~  s/(_)([^']+?)(_)(?{pos($string1) --})/$1'$2$3/go;
$string2 =~  s/(_)([^']+?)(_)(?{pos($string2) --})/$1'$2$3/go;

print "String 1: $string1 \n";
print "String 2: $string2 \n";

[download]

But somehow, this is not working for me and I get 
--output:--
String 1: _'nada_'komo_el_'sol_
String 2: _na'da_'komo_el_so'l_

[download]
Any ideas as to why this is happening?

Your wisdom is much appreciated ...

Pat

In reply to Re^2: Modifying the match position after each match by pat_mc
in thread Modifying the match position after each match by pat_mc

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