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A comment on Go 1.21 may have a clear(x) builtin.

Re:Go 1.21 may have a clear(x) builtin by martisch on Saturday November 19, 2022 @02:38PM (#33673792)
> This for loop is less efficient than clearing a map in one operation

For maps with keys that are reflexive with == the Go compiler already optimizes the range loop to a single efficient runtime map clear call: https://go-review.googlesource.com/c/go/+/110055

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Re:Go 1.21 may have a clear(x) builtin by tapirl on Saturday November 19, 2022 @11:33PM (#33678280)
Yes, for most cases, the for-loop is as efficient as the proposed "clear" function. I am not sure whether or not this is still true if there are NaN keys in the cleared map.
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