refactor(collection): !
overrides for unchecked iterator access
#10260
+6
−6
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Please describe the changes this PR makes and why it should be merged:
Currently, for backward compatibility reasons, when manually traversing builtin iterators, the type of
Iterator<T>.next().value
resolves toT | any
, or in other words, justany
.Under changes to iterators currently being planned for TypeScript 5.6, the resolved value type will change from
any
toT | void
in strict mode.There are a few instances in collection.ts where a result value no longer being
any
will cause issues. A test build shows the following errors:These errors fall into two categories:
T | void
.T
. It's therefore safe to use!
in these instances.reduce()
, if there's noinitialValue
provided thenInitialValue = Value
, so it's safe to force the accumulator type (in a similar vein to what already occurs inreduceRight()
).T | void
from a function that returnsT | undefined
. Although the void value is by definitionundefined
, this is an assignability error unless coerced.Status and versioning classification: