error[E0425]: cannot find value `abcd` in this scope
  --> $DIR/qquote.rs:25:38
   |
LL |     let expr = quote_expr!(&cx, 2 - $abcd + 7); //~ ERROR cannot find value `abcd` in this scope
   |                                      ^^^^ not found in this scope

error: aborting due to previous error

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