DSL EXPRESSION:
$i += 2


AST:
"block" [tt:block] [nt:StatementBlock]
    "+=" [tt:op_plus_equals] [nt:CompoundAssignment]
        "$i" [tt:field_name] [nt:DirectFieldValue]
        "+=" [tt:op_plus_equals] [nt:op_plus_equals]
        "2" [tt:int_literal] [nt:int_literal]

a   b   i x          y
pan pan 3 0.34679014 0.72680286
eks pan 4 0.75867996 0.52215111
wye wye 5 0.20460331 0.33831853
eks wye 6 0.38139939 0.13418874
