You can get the last match by adding .* in front of the regex.

If you use perl 5.10.0 or newer, you can make use of the \K ("keep") assertion: 

use 5.010;

my $str = '<1> <2> <3>';

$str =~ s/.*\K<\d>/<4>/;
say $str;
__END__
<1> <2> <4>

[download]

If you want to add test after the match, you can use s/.*<\d>\K/ <4>/ instead.

In reply to Re^3: How to start regexp from a X position (5.10 regex feature) by moritz
in thread How to start regexp from a X position by pkt

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