Exploring the Peano Axioms Through Algebraic Data Types

Re:Exploring the Peano Axioms Through Algebraic Data Types by jjaredsimpson on Tuesday January 15, 2019 @07:26PM (#18917162)

You swapped the order of method arguments though

you are doing x add Sy which isn't the same as Sy add x

        Number.prototype.add = function (y) {
          var x = Number(this)
          return x===0 ? y : (y+1).add(x-1)
        }

        console.log(Number(3).add(2)) // infinite

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Re:Exploring the Peano Axioms Through Algebraic Data Types by quietbritishjim on Thursday January 17, 2019 @11:47AM (#18932263)

Oops, sorry, I see what you mean now. You're right, it looks like this is a mistake:

    S: innerX => S(y).add(innerX)

It should be

    S: innerX => S(innerX).add(y)

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