warning: unnecessary parentheses around `return` value
  --> $DIR/path-lookahead.rs:18:10
   |
LL |   return (<T as ToString>::to_string(&arg)); //~WARN unnecessary parentheses around `return` value
   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
   |
note: lint level defined here
  --> $DIR/path-lookahead.rs:13:9
   |
LL | #![warn(unused)]
   |         ^^^^^^
   = note: #[warn(unused_parens)] implied by #[warn(unused)]

warning: function is never used: `with_parens`
  --> $DIR/path-lookahead.rs:17:1
   |
LL | fn with_parens<T: ToString>(arg: T) -> String { //~WARN function is never used: `with_parens`
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: lint level defined here
  --> $DIR/path-lookahead.rs:13:9
   |
LL | #![warn(unused)]
   |         ^^^^^^
   = note: #[warn(dead_code)] implied by #[warn(unused)]

warning: function is never used: `no_parens`
  --> $DIR/path-lookahead.rs:21:1
   |
LL | fn no_parens<T: ToString>(arg: T) -> String { //~WARN function is never used: `no_parens`
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^