Here's one method: 
perl -e "$s='OOO....MMMM..IIIII';$s=~s/(.)(\.+)/$1.$1 x length($2)/eg;
+print $s,$/;"
#            OOOOOOOMMMMMMIIIII

[download]

Or more appropriately for here: 

perl -e "$s='JJ..A....PPPP..HHHH...';$s=~s/(.)(\.+)/$1.$1 x length($2)
+/eg;print $s,$/;"
#            JJJJAAAAAPPPPPPHHHHHHH

[download]

In reply to Re: How to make these reg exp changes? by keszler
in thread How to make these reg exp changes? by Anonymous Monk

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