Here's a simple sed-like solution. This is probably not the fastest way, though. 

$string = "<<a> a> a <a>\n"; 
{ $string=~s/<([^<]*)>/\U$1/g and redo; }
print $string;

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In reply to Re: I don't remember regex seeming this hard before by ambrus
in thread I don't remember regex seeming this hard before by danderson

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