Unary operator precedence

[ghost]

Please add feature to adjust unary operator precedence so it will be possible to make following example works properly.
-x^2 and (-x)^2
gives

{
    type: "BinaryExpression",
    operator: "^",
    left: {
        type: "UnaryExpression",
        operator: "-",
        argument: { type: "Identifier", name: "x" },
        prefix: true
    },
    right: { type: "Literal", value: 2, raw: 2 }
}

I would like to add something like this:
jsep.addUnaryOp("-", 0);
So output of jsep() would be

{
    type: "UnaryExpression",
    operator: "-",
    argument: {
        type: "BinaryExpression",
        operator: "^",
        left: { type: "Identifier", name: "x" },
        right: { type: "Literal", value: 2, raw: 2 }
    },
    prefix: true
}

It would be only optional feature so IMO it will only improve library.

[mikeazo]

It would seem that in this case, JSEP mimics the behavior of Excel and Matlab. See Order of operations, special cases. It also happens if you input 2^3^2, which should parse as 2^(3^2) given typical mathematical right-associativity of exponentiation, but instead it parses as (2^3)^2.

[mikeazo]

This is probably a duplicate of #40