I tried but could not come up with one, if there is no underscore character in the string.
You should always show what you tried. Here's my shot from what I think you're saying 
$_ = 'a_c_code';

s{ ([^_]+) | (_) }'
   $2 ? " " : ucfirst $1
'gxe;
print $_,$/;

__END__
A C Code

[download]
You could also y/_/ / first, then s/(\w+)/\u$1/g;

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

In reply to Re: split and capitalize regex by PodMaster
in thread split and capitalize regex by arc_of_descent

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