Function native_grammar_concept_reuse 

pub fn native_grammar_concept_reuse() -> NativeConceptReuse

The per-language reuse report of the native grammars.

For every native grammar, its rules split into those that name a shared concept (one two or more native grammars name, listed with those languages) and those that name a concept specific to that language; and every concept the native grammars name with the languages that name it.