Dear Monks

Here is a script which replaces the last part of an URL 
#! /usr/bin/perl -l

my $url = "http://example.com/user/1234/" ;
$url =~ s![^/]+(?=/$)!_bla_! ;
print "URL = $url" ;

[download]
this works. However when I change the regex to 
s![^/]+(?=/)$!_bla_!

[download]
it doesn't!
Any suggestions why ?

cheers
LuCa

UPDATE: thnx a lot, I understand it now!!

In reply to regex issue (positive look-ahead) by jeanluca

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