{"ast_node_type":"function","tokens":[{"end":84,"kind":"keyword","start":0,"text":"fn"}]}
                fn fn_ctr_wrapped_2() fn() -> Result<Foo<T>, u32> [type_could_unify]
                fn fn_ctr_wrapped() fn() -> Option<Foo<T>> [type_could_unify]
                fn fn_other() fn() -> Option<u32> [type_could_unify]