What the straight line leaves out

Original deliberately incomplete diagram: File → Parse → Import → Done. It shows the happy path but does not define missing, unknown or ambiguous mappings.

Corrected rule diagram

Supplier mapping gatesMissing code is held. A present code is looked up. Zero matches is unmapped, one match proceeds to remaining validation, and more than one is ambiguous. Complete rules and examples follow as ordinary text.Input rowSupplier code present?Hold: missing codeLook up exact matches0: hold unmapped1: remaining validation>1: hold ambiguousNoYes01>1

Complete text equivalent

  1. If supplier code is missing, hold the row as missing; do not perform a lookup or import.
  2. If the code is present, look up its exact catalogue mappings.
  3. If there are zero matches, hold as unmapped.
  4. If there is one match, it is eligible for remaining validation. This is not a completed import.
  5. If there is more than one match, hold as ambiguous. Do not choose the first.
Four original synthetic branch cases
RowInputResult
R17S17 → C11,C12Hold ambiguous
R18S18 → C18Eligible for remaining validation
R19No supplier codeHold missing
R20S20 → no matchesHold unmapped

This is an authored contract illustration, not an importer execution or complete accessibility audit.