CurryInfo: icurry-3.2.0 / TermGraph.SVG.!?
definition: 
|
(!?) :: [a] -> Int -> Maybe a
[] !? _ = Nothing
(x:xs) !? i | i > 0 = xs !? (i-1)
| i == 0 = Just x
| otherwise = Nothing
|
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demand:
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argument 1 |
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deterministic:
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deterministic operation |
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documentation:
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Get index of a list and return it, if it exists. Return Nothing if not. |
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failfree:
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(_, _) |
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indeterministic:
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referentially transparent operation |
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infix:
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no fixity defined |
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iotype:
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{({[]},_) |-> {Nothing} || ({:},_) |-> {Just,Nothing}}
|
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name:
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!? |
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precedence:
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no precedence defined |
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result-values:
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{Just,Nothing}
|
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signature:
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[a] -> Prelude.Int -> Prelude.Maybe a |
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solution-complete:
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operation might suspend on free variables |
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terminating:
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possibly non-terminating |
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totally-defined:
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possibly non-reducible on same data term |