proposal: get child array instead of source array in UniqBy

[duc2h]

I think we should have a function to get child array instead of source array in UniqBy, for example:

I have an array students, I want to filter students who are duplicates and get their names only.

	students := []student{
		{
			Id:   1,
			Name: "student1",
		},
		{
			Id:   2,
			Name: "student2",
		},
		{
			Id:   1,
			Name: "student1",
		},
	}

The expectation result:

result = ["student1", "student2"]

If I use UniqBy it does not adapt to my case => I want another function that can help with that.