Wish I could tell the compiler to just use Expression

LiteralHint.swift

struct Expression : IntegerLiteralConvertible {
    let value: Int

    init(integerLiteral value: Int) {
        self.value = value
    }
}

struct Subexpression : IntegerLiteralConvertible {
    let value: Int

    init(integerLiteral value: Int) {
        self.value = value
    }
}

func * (lhs: Expression, rhs: Expression) -> Expression {
    return Expression(integerLiteral: lhs.value * rhs.value)
}

func * (lhs: Subexpression, rhs: Expression) -> Expression {
    return Expression(integerLiteral: lhs.value * rhs.value)
}

func * (lhs: Expression, rhs: Subexpression) -> Expression {
    return Expression(integerLiteral: lhs.value * rhs.value)
}

typealias DefaultIntegerType = Expression

let foo: Expression = 3*((4 * 3) as Expression)
let bar: Expression = 4 * 3