DSL EXPRESSION:
$x = 1 |  2 &  3


AST:
"block" [tt:block] [nt:StatementBlock]
    "=" [tt:equals] [nt:Assignment]
        "$x" [tt:field_name] [nt:DirectFieldValue]
        "|" [tt:op_bit_or] [nt:Operator]
            "1" [tt:int_literal] [nt:int_literal]
            "&" [tt:op_bit_and] [nt:Operator]
                "2" [tt:int_literal] [nt:int_literal]
                "3" [tt:int_literal] [nt:int_literal]

