FA-96073 / Postal address normalization / Member archive

Post office box canonicalizer: a prefix without a number falls through to street · case 03

"POST OFFICE BOX" alone is classified as a street line.

Member previewVariant 3 · 3 implementations · 11 checks per implementation

Case contract

Uppercase, turn periods into spaces and collapse whitespace. If the tokens start with one of the prefixes POST OFFICE BOX, P O BOX, PO BOX, POB, BOX (whole tokens) the line is a box line: exactly one alphanumeric identifier must follow, giving {"kind": "pobox", "line": "PO BOX ID"}, otherwise {"kind": "invalid", "line": cleaned}. Other lines return {"kind": "street", "line": cleaned}.

Why this case matters

Box addresses need different delivery handling from street addresses; misclassifying either breaks carrier selection and deduplication.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
trailing town after the box	`{"kind": "street", "line": "PO BOX 103 FAKETOWN"}`	`{"kind": "invalid", "line": "PO BOX 103 FAKETOWN"}`	Failed

MEMBER ARCHIVE

The complete case is available to members.

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

Member access is invitation-based. Sign in with your invited account to inspect the sources.