I have observed a surprising behaviour of map with closures. It seems that type instabilities appear when the function called by map overwrites a variable that belongs to an outer scope (only changing its value while keeping the same type). Here is a MWE: function map_bad(x) r = rand(typeof(fir…

https://docs.julialang.org/en/v1/manual/performance-tips/#man-performance-captured

Type instability when using map with closures

mrufsvold July 12, 2023, 7:49am 3

You can also read The Great Debate if you want to get into the weeds!

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