warning: unnecessary parentheses around `return` value
  --> $DIR/path-lookahead.rs:8:10
   |
LL |   return (<T as ToString>::to_string(&arg));
   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
   |
note: lint level defined here
  --> $DIR/path-lookahead.rs:3:9
   |
LL | #![warn(unused)]
   |         ^^^^^^
   = note: #[warn(unused_parens)] implied by #[warn(unused)]

warning: function is never used: `with_parens`
  --> $DIR/path-lookahead.rs:7:1
   |
LL | fn with_parens<T: ToString>(arg: T) -> String {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: lint level defined here
  --> $DIR/path-lookahead.rs:3:9
   |
LL | #![warn(unused)]
   |         ^^^^^^
   = note: #[warn(dead_code)] implied by #[warn(unused)]

warning: function is never used: `no_parens`
  --> $DIR/path-lookahead.rs:11:1
   |
LL | fn no_parens<T: ToString>(arg: T) -> String {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^