syntax_data: {"ast_node_type":"other","tokens":[{"end":81,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // The callee is something implementing Fn, FnMut, or FnOnce.
context_before:                 if self.typeck_results.is_method_call(expr) {
context_after:                     // Find the actual method implementation being called and