Defer mapped type indexed access transformations #18042
Merged
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With this PR we defer certain mapped type indexed access transformations. Previously, we'd eagerly transform an indexed access of the form
{ [P in K]: T}[X]
into an instantiation ofT
whereX
is substituted for every occurrence ofP
. We now keep the original form and instead perform the transformation as we obtain the constraint of the indexed access.Fixes #15756.