[vector] #28: Add safe indexing function

[vector]

#28: Add safe indexing function
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Reporter:  anonymous    |       Owner:     
    Type:  enhancement  |      Status:  new
Priority:  major        |   Milestone:     
 Version:               |    Keywords:     
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 Please add safe indexing function which doesn't bombs when index goes out
 of range. Such function is very convenient when it's known that indices
 may go out of range. I think such function deserve inclusion in library.

 {{{
 (!?) :: Vector v a => v a -> Int -> Maybe a
 }}}

-- 
Ticket URL: <http://trac.haskell.org/vector/ticket/28>
vector <http://trac.haskell.org/vector>
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