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Definite initialization at a branch join retains one-arm facts · case 04

Definite initialization at a branch join retains one-arm facts.

Member previewVariant 4 · 3 implementations · 13 checks per implementation

Case contract

Static path initialization lattice for a record with declared leaf names. Commands init/move/read/whole/assign/drop/reset/copy/merge/available. init and assign initialize one leaf. move consumes only initialized named leaf and reports success; read tests one; whole tests all. drop consumes all and reports previously initialized names. reset clears; copy tests without consumption. merge intersects current initialized leaves with supplied branch leaves. available returns sorted initialized names. Unknown leaves never initialize. Return one result per command. This is definite-initialization analysis, not runtime borrowing.

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
join intersection	`[["a"], ["a", "b"], ["a", "b"]]`	`[["a"], [], []]`	Failed

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