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A single mutated capture fails to upgrade closure call capability · case 05

A single mutated capture fails to upgrade closure call capability.

Member previewVariant 5 · 3 implementations · 21 checks per implementation

Case contract

Validate an inferred closure environment. Captures contain declared places; overlapping prefix captures must be minimized; unique captures may not be duplicated; consumed captures require Once call mode; mutated captures require Mut or Once; an escaping environment cannot hold stack-only origins; environment region contains all call sites; captured references remain valid for the environment region; captures of packed fields cannot form references; captures of destructor-bearing aggregates cannot be narrowed to moved fields. 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
mut-mode regression 0	`[]`	`["mut-mode"]`	Failed

MEMBER ARCHIVE

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