error[E0425]: cannot find function `len` in this scope
  --> $DIR/suggest-method-on-call-with-macro-rcvr.rs:4:17
   |
LL |     let hello = len(vec![]);
   |                 ^^^ not found in this scope
   |
help: use the `.` operator to call the method `len` on `&Vec<_>`
   |
LL -     let hello = len(vec![]);
LL +     let hello = vec![].len();
   |

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0425`.