{"ast_node_type":"function","tokens":[{"end":74,"kind":"keyword","start":0,"text":"fn"}]}
    fn pat_is_irrefutable(&self, decl_ctxt: Option<DeclContext>) -> bool {
    /// the slice impl candidate would be rejected anyway (if no ambiguity existed).
        matches!(decl_ctxt, Some(DeclContext { origin: DeclOrigin::LocalDecl { has_else: false } }))