Lots of good solutions here. If you can clearly isolate the thing you want to change, you can keep it pretty simple and control the number of changes with $i: 
$x = 'ababababab';
$i=3;
$x =~ s/(^|[^a])a([^a]|$)/$1B$2/ while $i--;
print "$x\n"
__END__

BbBbBbabab

[download]
--marmot

In reply to Re: Does Perl support a given number of replacements ? by furry_marmot
in thread Does Perl support a given number of replacements ? by Anonymous Monk

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