Go-optics. Modifying immutable data types in Go. #

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	//Create a nested immutable data structure.
	data := NewBlogPost(
		"BlogPost",
		[]Comment{
			NewComment("First Comment", "First comment content"),
			NewComment("Second Comment", "Second comment content"),
		},
	)

	//Create an optic to focus the first comments content.
	optic := O.BlogPost().Comments().Nth(0).Content()

	//Set a new value to the focused comment.
	newData := MustSet(
		optic,
		"Updated comment content",
		data,
	)

	fmt.Println(newData)
	//Output:
	//{BlogPost [{First Comment Updated comment content} {Second Comment Second comment content}] []}