Operator on tuple

[20chan]

Like Nullable supports operators defined at T, Tuple can be.

Example:

void DoSomething((int x, int y) c1, (int x, int y) c2)
{
    int (a, b) = (c1.x + c2.x, c1.y + c2.y);
    (a, b) = (-a, -b);
}

Could be

void DoSomething((int x, int y) c1, (int x, int y) c2)
{
    int (a, b) = c1 + c2;
    (a, b) = -(a, b);
}

Even if types of all elements in tuple is not identical operator can be used if all types override specific operator.

(int a, string b) = (1, "Hello, ") + (10, "World!");

[bondsbw]

Would applying the operator to tuples of different lengths be allowed? If so, what would be the runtime behavior?

[20chan]

Forgot that one. Lengths of tuples must be same and it will be checked when compiling.

[bondsbw]

Related: #190

[stakx]

Which binary operators are you thinking of here? Just + and -, or also others like &, |, ^, %?

If this makes it into the language, it might not take long until someone suggests k * (a, b, c , ...) where k is a single value. Should this be allowed too and translated as (k * a, k * b, k * c, ...)?

[Unknown6656]

@stakx : Yes, please!!
And IMO it should be allowed on all binary and unary operators.

[quinmars]

@stakx and what happens if the single value of k is (1, "Hello, ")? 😄

[stakx]

@quinmars - I think you know how I meant it. 😆 But for the record, let's say "where k is not a tuple".

In fact, with the above I wanted to show that this proposal for operator + on tuples could quickly grow into something bigger, and not every other operator's workings might be as easy to decide as +. For example, would there be any real-world use for short-circuiting operators such as && applied to tuples? What would unambiguous syntax look like for the application of some explicit operator T(<tuple type>)? etc.

I do like this proposal, but I can't help but wonder whether the request for these kind of operations on tuples have a mostly numerical / mathematical background, in which case it might be better to use System.Numerics.Vectors et al. instead of tuples...?

[bondsbw]

A tuple is not a mathematical vector, and we should be careful not to confuse the two.

[jnm2]

This is in line with the principle that operations on a tuple should be distributive to its elements. I like it.