syntax_data: {"ast_node_type":"other","tokens":[{"end":92,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // If this is a virtual call, we cannot pass the `fn_def_id`, as it might call other
context_before:         sig.abi,
context_after:         // functions from vtable. Internally, `deduced_param_attrs` attempts to infer attributes by