Qualification that attaches to a specific component.

Emitted as {unit_qualification: qualifier} so that downstream consumers can identify which component is being qualified (e.g. {:year_qualification, :uncertain}).

Merge a trailing {:qualification, _} token into the preceding tagged date/datetime/time inner list. Used by the :qualified_endpoint parsec to keep each interval endpoint and its qualification paired.

Returns a single tuple so that the reduce emits one value into the enclosing parser accumulator, matching the shape emitted by parsec(:datetime_or_date_or_time) when no qualifier is present.

ISO 8601-2 / EDTF qualification suffix.

? marks a date as uncertain (the value is a best guess). ~ marks it as approximate (the value is approximately correct, e.g. "circa 1850"). % marks both.