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A common field prefix suppresses later disjointness · case 03

A common field prefix suppresses later disjointness.

Member previewVariant 3 · 3 implementations · 13 checks per implementation

Case contract

Places are lists of projections: root name, then fields or integer indices. Different roots and unequal fields or known indices are disjoint. A wildcard index ? aliases any index. A union projection | overlaps any sibling. Dereference * conservatively overlaps another projection at that depth. Prefix places overlap; empty denotes no place. Return overlap.

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
shared prefix	`true`	`false`	Failed

MEMBER ARCHIVE

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