Map/IntMap: Document the most common O(n²) performance mistake #961
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This documents the single most common performance mistake when dealing with
containers
.I have seen professional Haskellers, get it wrong or wonder about it countless times, and the only hint in the entire module space on how the function
f :: a -> a -> a
is applied is on the docs ofinsertWith
, which is not where anybody looks when checking the docs of any of these functions.