Function sum`Const`

sum(): (src: Iterable) => number
Calculates the arithmetic sum of all numbers in the source iterable.

Curried version of _sum.

Returns (src: Iterable) => number
Total of all elements in src, or 0 when the iterable is empty.
Example
```
const total = _sum([1, 2, 3, 4]);
console.log(total); // 10
```
or using the curried version:
```
const total = pipeInto([1, 2, 3, 4], sum());
console.log(total); // 10
```