vlib/v/parser/tests/multi_argumented_assign_err.vv:3:10: error: unexpected +=, expecting := or = or comma
    1 | fn main() {
    2 |     mut a, mut b, mut c := 0,1, 2 
    3 |     a, b, c += 1, 2, 4
      |             ~~
    4 |     println('${a} ${b} ${c}')
    5 | }