Go - Creating Stacks

Problem: You want to create a stack data structure.

Solution: Wrap a struct around a slice. Create stack functions on the struct.

 

A stack is a last-in-first-out (LIFO) ordered list. You add elements at the top of the stack and get elements from the top of the stack as well.

Stacks are very important in programming, especially in memory management. They’re also used for creating recursive functions, expression, evaluation, and backtracking.

Here are the functions associated with a stack:
Push
• Add an element to the top of the stack.
Pop
• Remove an element at the top of the stack.
Peek
• Get the element at the top of the stack without removing it.
Size
• Get the size of the stack.
IsEmpty
• Check if the stack is empty.

There are a few ways to implement a stack but here you’ll simply be using a single slice:

type Stack struct {
    elements []any
}

func (s *Stack) Push (el any) {
    s.elements = append(s.elements, el)
}

func (s *Stack) Size() int {
    return len(s.elements)
}

func (s *Stack) IsEmpty() bool {
    return s.Size() == 0
}

func (s *Stack) Pop() (el any, err error) {
    if s.IsEmpty() {
        err = errors.New("empty stack")
        return
    }
    el = s.elements[len(s.elements) - 1]
    s.elements = s.elements[:len(s.elements) - 1]
    return
}

func (s *Stack) Peek() (el any, err error) {
    if s.IsEmpty() {
        err = errors.New("empty queue")
        return
    }
    el = s.elements[len(s.elements) - 1]
    return
}