{"ast_node_type":"other","tokens":[{"end":65,"kind":"keyword","start":0,"text":"(Pure)"}]}
    (Pure)           => { exp!(@sym, pure,            SymPure) };
    (PreservesFlags) => { exp!(@sym, preserves_flags, SymPreservesFlags) };
    (Readonly)       => { exp!(@sym, readonly,        SymReadonly) };