Great idea (idiom, actually)!
But, errr, here's a "no-setup" solution of your combined grep and index problem: 
print( ("|","*"," ")[ $seen && 2 || ($seen = $_ eq $pos) ], " $_\n" ) 
+for @list;

[download]


p

In reply to Re: = - not only for sort anymore by petral
in thread <=> - not only for sort anymore by Corion

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