Perhaps a programmatic pattern?

johngg@aleatico:~/perl/Monks$ perl -Mstrict -Mwarnings -E 'say q{};
my $text = <<__EOT__;
cat
dog
cat
mouse
eel
cat
housecat
catamaran
fish
__EOT__

my $n = 0;
$text =~ s{cat(?{ $n++ })}{$n}g;
say $text;'

1
dog
2
mouse
eel
3
house4
5amaran
fish

[download]

I hope this is helpful.

Cheers,

JohnGG

In reply to Re: Perl substitute with the nth match by johngg
in thread Perl substitute with the nth match by misterperl

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