DSL EXPRESSION:
$x = 123. + 1e-2 / .2e3 + 1.e-3 + 2e+1


AST:
"block" [tt:block] [nt:StatementBlock]
    "=" [tt:equals] [nt:Assignment]
        "$x" [tt:field_name] [nt:DirectFieldValue]
        "+" [tt:op_plus] [nt:Operator]
            "+" [tt:op_plus] [nt:Operator]
                "+" [tt:op_plus] [nt:Operator]
                    "123." [tt:float_literal] [nt:float_literal]
                    "/" [tt:op_slash] [nt:Operator]
                        "1e-2" [tt:float_literal] [nt:float_literal]
                        ".2e3" [tt:float_literal] [nt:float_literal]
                "1.e-3" [tt:float_literal] [nt:float_literal]
            "2e+1" [tt:float_literal] [nt:float_literal]

