Why not just show the out-of-range index?

[Tim Chase]

>> - because error messages are not debugging tools (better use unit
> 
> Then what are they? Machine-generated poetry?

 >>> me.__cmp__(gruntbuggly['freddled'].micturations, 
bee[LURGID].gabbleblotchits[PLURDLED]) == 0

Traceback (most recent call last):
   File "<stdin>", line 1, in ?
VogonPoetryException: Bleem miserable venchit! Bleem forever 
mestinglish asunder frapt!


Nah...Exceptions aren't poetry...they're programmer insults akin 
to "You fool!  How could you have let this happen!"  And if 
things are really bad, exceptions call you "silly" :*)

-tkc