Support merge generators

[SettingDust]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

Support merge generators

Motivation

No response

Example

const values1 = function * () {
  yield * [0, 1, 2, 3, 4]
}
const values2 = function * () {
  yield * [5, 6, 7, 8, 9]
}

deepmerge(values1, value2) // generator like 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 <- ordered

const values1 = async function * () {
  yield * [0, 1, 2, 3, 4]
}
const values2 = async function * () {
  yield * [5, 6, 7, 8, 9]
}

deepmerge(values1, value2) // async generator like 0, 1, 5, 2, 6, 7, 3, 4, 8, 9 <- no order

[mcollina]

I think this should be a separate function than the main deepmerge.

Overall, I think this might be better implemented as a new utility module.

[Uzlopak]

I wonder how to do it. Lets assume we can detect generators. Maybe that the generator function is async.

What are you doing in case of three or more generator functions getting merged? Do you round robin it? What if the generator functions are yielding at different "times"? What if there are some serious side effects, that you need to take in consideration, and not "blindly" call the generator function

Ok, lets say we use your example, that you then just basically do:

let i = 0
const combinedValues = async function * () {
  if (i % 2 === 0) {
    yield await values1()
  } else {
    yield await values2()
  }
}

What if values1 is shorter than values2? Do you then need to call values2?

Maybe it makes sense to see if it is possible to implement something like JSON.parse/.stringify has like reviver or replaced, and make it a super strong "hook".

Then you maybe could pass some function which gets both elements from source and target and then you can do any magic you want.

[mcollina]

I think we can close this as out-of-scope. Wdyt?