rustc_const_eval::const_eval::fn_queries

Function constness

Source 
fn constness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Constness
Expand description

Checks whether an item is considered to be const. If it is a constructor, it is const. If it is an assoc method or function, return if it has a const modifier. If it is an intrinsic, report whether said intrinsic has a rustc_const_{un,}stable attribute. Otherwise, panic.