warning: unnecessary parentheses around `return` value
  --> $DIR/path-lookahead.rs:10:12
   |
LL |     return (<T as ToString>::to_string(&arg));
   |            ^                                ^
   |
note: the lint level is defined here
  --> $DIR/path-lookahead.rs:5:9
   |
LL | #![warn(unused_parens)]
   |         ^^^^^^^^^^^^^
help: remove these parentheses
   |
LL -     return (<T as ToString>::to_string(&arg));
LL +     return <T as ToString>::to_string(&arg);
   |

warning: 1 warning emitted