Reading a bill

Document::open or Document::parse reads a file of any GAEB DA XML version from 3.0 to 3.3. The version and phase come from the namespace first, then from GAEBInfo/Version and Award/DP, then from the file extension; every guess is a warning you can read in doc.warnings.

The typed tree is doc.gaeb: one struct per schema type, strings as spans resolved with doc.str(span), decimals as Decimal. Most callers never touch it and use the navigation layer instead:

• doc.items() yields every item in document order with its Oz (the Ordnungszahl formed from the BoQBkdn levels), its kind, quantity, unit, prices and texts, plus the categories above it in path.
• doc.categories() yields the LV-Bereiche with label, depth and declared totals.
• doc.markup_items() yields Zuschlagspositionen.
• doc.computed_totals() sums items per Fachdokumentation 4.6.17 and puts the result next to what the file declares.

Kinds of items

ItemRef::kind() tells a Standard item from a LumpSum, a Bedarfsposition with or without Gesamtbetrag (ProvisionalWithTotal, ProvisionalWithoutTotal), a Grundposition (Base) and its alternatives (Alternative { group, serial }), hourly and key items, a free quantity the bidder fills in, and a not-applicable item. counts_towards_total() applies the standard’s rule: alternatives, Bedarfspositionen ohne GB, not-applicable and not-offered items stay out of the sums, whatever else they are.

Ordnungszahl

item.oz.dotted() prints 001.002.0010A: levels zero-padded to their declared width (or space-padded per alignment for non-numeric levels), joined by dots, the index appended directly; a skipped level shows as _. compact() gives the fixed-width form, trade() the first level, lot() the lot when the breakdown starts with one.