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A phantom ownership marker incorrectly freezes lifetime covariance · case 02

A phantom ownership marker incorrectly freezes lifetime covariance.

Member previewVariant 2 · 3 implementations · 12 checks per implementation

Case contract

Infer lifetime parameter variance in a toy type tree. Variance signs are +1 covariant, -1 contravariant, 0 invariant; repeated different signs join to invariant. var(name); ref(lifetime,type) covariant both; mut(lifetime,type) covariant lifetime invariant payload; fn(argument,result) flips argument; tuple(list) joins; cell(type) invariant; phantom(type) covariant; array(type,length) covariant; opaque(parameters) invariant for every listed parameter; unused(name) contributes nothing. Return parameter-to-sign map.

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
phantom	`{}`	`{"a": 1}`	Failed

MEMBER ARCHIVE

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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