Add support for tuple operations

[GaspardCulis]

Add support for Add and Sub operations on Value::Tuple.

• I publish this contribution under the MIT License.

[ISibboI]

This is a great idea, but should we use builtin functions instead of operators for this? Because for strings, the + operator indicates concatenation. So for tuples, users may also expect it to mean concatenation. I would propose function names piecewise_add and piecewise_sub.

[GaspardCulis]

Hi, thanks for the feedback! My idea was that the Tuples would just apply the opcode to each of the tuple element pairs (granted the two tuples have the same length). For now it works with Add and Sub, but I was also imagining multiplication and divison (every operator with two arguments really). We could also add support for single argument operators, where the operator is again, applied to each tuple element. And to my opinion the builtin functions should be used for less common operations, like concat, or maybe also the dot_product.

Please tell me your thoughts and I'll try to implement those as best as I can :)