Cascade.IndexSourceExact declaration-to-row index.
Immutable index from declarations to sorted row ids.
val v :
?same:(Declaration.t -> Declaration.t -> bool) ->
?keep:(Stylesheet.rule -> bool) ->
Stylesheet.rule array ->
tv ?same ?keep rules indexes declarations from rules accepted by keep. Duplicate declarations within one rule contribute that row only once.
rows t decl returns the sorted row ids that contain decl. It returns an empty array when decl is absent.
iter t f calls f decl rows for each indexed declaration. rows is sorted ascending and contains no duplicate row ids.