A negative look behind asserion will do the trick, see perlman:perlre on lookahead and look behind assertions both positive and negative for more details. 

$_ = 'c:--->j:a:p:h:,:';
s/(?<![cC]):/!/g;
print;

[download]
You could just use 'C' instead of the character class [cC] which makes this case insensitive. Of course you could also use /i at the end to do this but the character class was included in case you want to skip stuff like D:....

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Is there a way I can substitute for ":" except when it is preceded by a letter C by tachyon
in thread Is there a way I can substitute for ":" except when it is preceded by a letter C by kirk123

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