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Repeated occurrences of one lifetime parameter receive different actual regions · case 02

Repeated occurrences of one lifetime parameter receive different actual regions.

Member previewVariant 2 · 3 implementations · 21 checks per implementation

Case contract

Check generic borrow-summary instantiation. Generic lifetime arguments match parameter arity; parameter substitution is positional; repeated occurrences substitute consistently; recursive instantiation uses each callee actual mapping; static lifetime is not substituted; inferred anonymous lifetimes are fresh per call; where-outlives obligations instantiated in declared direction; associated lifetime applications include all type arguments; recursive summary fixed point cannot be accepted while new obligations remain; monomorphized reference types retain lifetime proof metadata. Input is a fully explicit descriptor of the stated toy IR. Return rule identifiers in declaration order; absent optional obligations use the provided neutral defaults. No rule is an assertion about a production language.

Why this case matters

A finite offline static-analysis model of ownership and borrowing; it does not execute the analyzed program.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
repeated-substitution regression 0	`[]`	`["repeated-substitution"]`	Failed

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