Dear All, I wish to insert a new line every two digits. Thought I'd use look-behind to do this: 
my $x=12345;
$x=~s/(?<=\d{2})/\012/g;
print $x,"\n";

[download]
I get: 
12
3
4
5
I know I can do this other ways, but the result has left me confused as to what is going on with the look behind with the global modifier. Surely at position 3 the look behind 'sees' 12\n? No? Any explanation would be appreciated many thanks james

In reply to Look behind and global by gingaloon

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