Allow arithmetic operations on tables (`+`, `-`, `*` and `/`)

[EwoutH]

It would be very useful to be able to use arithmetic operations (+, -, * and / and potentially more) directly on tables.

let fruit table:make
table:put fruit "apple" 2
table:put fruit "orange" 5
table:put fruit "banana" 3

So set fruit fruit + 1 would be allowed for example , which increases all the values in the table by one.

[brandesNW]

Do you have a use case for this?
Would this produce an error if any value was non-numeric?
If a key has a numeric value in one table and is absent in the other what happens?

If a key has a numeric value in one table and a non-numeric one in the other what happens? is it an error, or is the key just omitted?
Similarly for both values non-numeric?

[EwoutH]

Do you have a use case for this?

Two examples:

• If you have a table with counters, it's very useful to add one to them every tick.
• If you want to normalize your numbers, you can divide all by the maximum number in the table (especially powerful together with table:max-value and table:max-key to get the maximum value and key of the maximum value from a table #15).

If a key has a numeric value in one table and a non-numeric one in the other what happens? is it an error, or is the key just omitted?

I think an error can be expected on non-numeric values.