make

The make() function allows us pre-allocate backing array of a slice with a given length and capacity.

make([]int, 3) // [0 0 0] len - 3, cap - 3

make() initializes and returns a slice with the given length/capacity. []int is the type of the slice. 3 reps the length and capacity of the slice.

We can also create a slice with different length and capacity. This is needed when we want to use only some parts of a slice.

make([]int, 3, 5) // len - 3, cap - 5

when the length is 0, the make() will return a slice ready to append.

make([]int, 0, 5) // len - 0, cap - 5

NOTE: We only use make() when we want to optimize our software or pass a limited slice size to some function.