LifetimeDependence: Disable parameter indices in Swift lifetime dependence annotations#86846
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Rebased on top of #86842, ignore all but the last commit. |
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Lifetime indices are never necessary in Swift, they unnecessarily expose implementation details, and they make lifetime annotations more error-prone, since they may need to be updated if a function's parameter list changes. The Swift Syntax parser also cannot handle lifetime annotations where the target is an index. The main reason the C++ parser supports them is because it is also used for SIL.
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Parameter indices are never necessary in Swift lifetime syntax, they unnecessarily expose implementation details, and they make lifetime annotations more error-prone, since they may need to be updated if a function's parameter list changes.
Indices were only ever mentioned in the lifetimes proposal as an alternative spelling that could be added in response to sufficient demand, so this should not break any code using the feature as documented (confirmed by a manual search of internal codebases).