Optimize Function0 allocations
#2366
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ghostdogpr
reviewed
Aug 19, 2024
ghostdogpr
approved these changes
Aug 19, 2024
ghostdogpr
approved these changes
Aug 19, 2024
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This PR optimizes (mostly)
Function0allocations that originate frommap.getOrElse(key, ???). In Scala 2, the optimization is fairly straight-forward; we just need to store the default value in aFunction0. Since=> Acompiles to() => A, this means that invocations of thegetOrElse(key, DefaultValueFn())don't create aFunction0.In Scala 3 however, it's slightly more complex. For some reason (might be a bug, I'll open an issue in Dotty about it), this works only if the val is annotated with
@static, which compiles to afinal staticfield. To avoid having to do this everywhere, I added a package-privatesyntaxobject with thegetOrElseNullmethod.I've also noticed some small optimizations that could be done here and there so I did them as part of this PR