Number vs Float/Int

[Namek]

AFAIK the language supports only the Number type for numbers. However, quite often I define indices in my code. I want to make sure that index is an integer. Another case is having an amount of items.

Are you against having this distinction and if yes then why?

[gdotdesign]

The reason it only supports Number type because in JavaScript there is only number.

I think Number is good in the general but I'm not against having an Int (or Integer) type beside that. Implementation wise I don't know if it's enough to have a module for it or it needs compiler support.

[Namek]

Initially I thought about splitting between Float and Int but having the current Number and an additional Int sounds good to me.

I propose:

1. support Int as a type, I don't think that a sole module is enough
2. redefine Math.floor()/Math.ceil() to return Int
3. when doing math (+, -, /, *, %) between Number and Int would require an explicit conversion. Int.toNumber(n : Number) : Int and the Math functions from above. Maybe additional Number.toInt(n : Number) : Int.

[gdotdesign]

I think what you suggest can be done relatively easily, what we have to think about what operations would return in each case, this is what I got so far:

• +, -, * if any operands are Number it would return Number, if all operants are Int it would return Int
• / would only work on Number / Number
• // would only work on Int / Int (Integer division. The remainder is discarded.) (needs to be a function in the runtime)
• % I need to look it up how it behaves in other languages

In addition it would be nice to have an operator for https://en.wikipedia.org/wiki/Modular_arithmetic

NumberLiterals would have the Number type unless otherwise stated property index : Int = 0 (in this case if a decimal is specified it would raise an error)

Under the hood it would all use the JavaScript Number type unless we use BigInt which I don't recommend since it's support is only 70% https://caniuse.com/#feat=bigint

[Sija]

If we're to introduce Int type, I'd strongly suggest to add a Float counterpart - and both would descend from Number.

Distinction Int / Number on its own seems counter-intuitive.

[Namek]

If we're to introduce Int type, I'd strongly suggest to add a Float counterpart - and both would descend from Number.

Distinction Int / Number on its own seems counter-intuitive.

@Sija Can you explain why would that be counter-intuitive?

[Sija]

@Sija Can you explain why would that be counter-intuitive?

Because they mix the entities from two different levels - Number can be seen as the most general type, whereas Int, Float and possibly others, like BigDecimal are more concrete variants of it. Does saying out loud Number.toInt makes sense? That's what I meant by counter-intuitive. Float.toInt OTOH sounds pretty obvious to me re: the logic and function behind.

[danhowardms]

I disagree with this. I think adding Float as a separate thing would add more confusion because it would be identical to Number. You have a perfect one-to-one correspondence between all the possible Floats and all the possible Numbers, and the exact same behaviour in functions and operations.

Int and Float are not at the same 'level' as each other, because every Int is also a Float but only some Float values are also Int.

Float and Number are at the same 'level' because every Float is a Number and every Number is also a Float.

The distinction between Int and Float in other languages reflects the underlying binary representation, but that distinction is invalid here where the underlying representation for both would be javascript's Number (which is an IEEE754 double-precision float).

Does saying out loud Number.toInt makes sense? That's what I meant by counter-intuitive. Float.toInt OTOH sounds pretty obvious to me

Neither of those sound very logical to me. What would Float.toInt(0.4) be? floor(), ceil() and round() make perfect sense when applied to any Number and always give you a Number which happens to also be an Int.