You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

43 lines
836 B

package femto
// Stack is a simple implementation of a LIFO stack for text events
type Stack struct {
Top *Element
Size int
}
// An Element which is stored in the Stack
type Element struct {
Value *TextEvent
Next *Element
}
// Len returns the stack's length
func (s *Stack) Len() int {
return s.Size
}
// Push a new element onto the stack
func (s *Stack) Push(value *TextEvent) {
s.Top = &Element{value, s.Top}
s.Size++
}
// Pop removes the top element from the stack and returns its value
// If the stack is empty, return nil
func (s *Stack) Pop() (value *TextEvent) {
if s.Size > 0 {
value, s.Top = s.Top.Value, s.Top.Next
s.Size--
return
}
return nil
}
// Peek returns the top element of the stack without removing it
func (s *Stack) Peek() *TextEvent {
if s.Size > 0 {
return s.Top.Value
}
return nil
}