v0.0.61

dataext/stack.go

@@ -0,0 +1,98 @@
+package dataext
+
+import (
+	"errors"
+	"gogs.mikescher.com/BlackForestBytes/goext/langext"
+	"sync"
+)
+
+var ErrEmptyStack = errors.New("stack is empty")
+
+type Stack[T any] struct {
+	lock *sync.Mutex
+	data []T
+}
+
+func NewStack[T any](threadsafe bool, initialCapacity int) *Stack[T] {
+	var lck *sync.Mutex = nil
+	if threadsafe {
+		lck = &sync.Mutex{}
+	}
+	return &Stack[T]{
+		lock: lck,
+		data: make([]T, 0, initialCapacity),
+	}
+}
+
+func (s *Stack[T]) Push(v T) {
+	if s.lock != nil {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+	}
+
+	s.data = append(s.data, v)
+}
+
+func (s *Stack[T]) Pop() (T, error) {
+	if s.lock != nil {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+	}
+
+	l := len(s.data)
+	if l == 0 {
+		return *new(T), ErrEmptyStack
+	}
+
+	result := s.data[l-1]
+	s.data = s.data[:l-1]
+
+	return result, nil
+}
+
+func (s *Stack[T]) OptPop() *T {
+	if s.lock != nil {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+	}
+
+	l := len(s.data)
+	if l == 0 {
+		return nil
+	}
+
+	result := s.data[l-1]
+	s.data = s.data[:l-1]
+
+	return langext.Ptr(result)
+}
+
+func (s *Stack[T]) Peek() (T, error) {
+	if s.lock != nil {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+	}
+
+	l := len(s.data)
+
+	if l == 0 {
+		return *new(T), ErrEmptyStack
+	}
+
+	return s.data[l-1], nil
+}
+
+func (s *Stack[T]) OptPeek() *T {
+	if s.lock != nil {
+		s.lock.Lock()
+		defer s.lock.Unlock()
+	}
+
+	l := len(s.data)
+
+	if l == 0 {
+		return nil
+	}
+
+	return langext.Ptr(s.data[l-1])
+}