syntax_data: {"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":"CanonicalVarKind::PlaceholderConst(placeholder)"}]}
source_snippet:             CanonicalVarKind::PlaceholderConst(placeholder) => placeholder.universe(),
context_before:             CanonicalVarKind::PlaceholderRegion(placeholder) => placeholder.universe(),
context_after:             CanonicalVarKind::Ty(CanonicalTyVarKind::Float | CanonicalTyVarKind::Int) => {