http://www.perlmonks.org?node_id=1067905


in reply to Lookahead/Lookbehind Regular Expression...

I wouldn't bother with look-ahead/behind on this problem: 
$_ = 'u.s. asdf.g. and i.  M.C. Escher and P. Picasso';
s/\b(\w)\.(\w)\./$1$2/g;
# $_ eq 'us asdf.g. and i.  MC Escher and P. Picasso'

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