Document auto-numbering: three systems, sixteen part types, and freezing
sources/autoNum/ is ~5,085 lines, and the only wiki pages mentioning it
were 7-to-9-line XML reference stubs describing where it is stored.
Covers what a scheme actually is -- an ordered list of parts -- and all
sixteen part types: seven counters (with the per-folio variants and wrap's
modulus), seven context parts that take their value from the element's
position or folio, and string/alpha. Documents that format overrides the
type's natural zero-padding, and that alpha increments like a spreadsheet
column name.
The behaviours that surprise people and were written down nowhere:
- a scheme supplies sequences, a formula places them, and a %sequ_N whose
index the scheme does not define prints itself verbatim with no warning
- a new conductor joining an existing potential inherits its number; only
a genuinely new potential draws a fresh one, and a potential whose
conductors disagree opens the potential selector
- folio variables in a conductor formula resolve per conductor, not per
potential
- freezing exists at three scopes (project, folio, item), which is why a
project can hold labels that no longer match their formula
- a scheme with an empty title or formula is silently dropped on save
Also notes that terminal numbering is a separate feature honouring
auto_num_locked. EN/FR/DE.