What are the consequences of using the append method for a slice declared without initial parameters?

If a slice in Go is declared without initial parameters, for example var s []int, then it is initially equal to nil and does not point to an allocated array. When using the append function, Go automatically allocates a new array and adds elements to it, returning a new slice with the required capacity.

This means that append safely works with nil slices, and you can write:

var s []int // nil slice
s = append(s, 1, 2, 3) // now s points to a new array with elements

Consequences:

• There is no need to initialize a slice before using append.
• The first call to append allocates memory.
• If the slice is nil, then len(s) == 0 and cap(s) == 0.

Thus, using append with a nil slice is standard practice in Go, which simplifies working with dynamic collections.