status-go/vendor/github.com/ethereum/go-ethereum/common/prque/prque.go

58 lines
1.4 KiB
Go
Executable File

// This is a duplicated and slightly modified version of "gopkg.in/karalabe/cookiejar.v2/collections/prque".
package prque
import (
"container/heap"
)
// Priority queue data structure.
type Prque struct {
cont *sstack
}
// Creates a new priority queue.
func New(setIndex setIndexCallback) *Prque {
return &Prque{newSstack(setIndex)}
}
// Pushes a value with a given priority into the queue, expanding if necessary.
func (p *Prque) Push(data interface{}, priority int64) {
heap.Push(p.cont, &item{data, priority})
}
// Pops the value with the greates priority off the stack and returns it.
// Currently no shrinking is done.
func (p *Prque) Pop() (interface{}, int64) {
item := heap.Pop(p.cont).(*item)
return item.value, item.priority
}
// Pops only the item from the queue, dropping the associated priority value.
func (p *Prque) PopItem() interface{} {
return heap.Pop(p.cont).(*item).value
}
// Remove removes the element with the given index.
func (p *Prque) Remove(i int) interface{} {
if i < 0 {
return nil
}
return heap.Remove(p.cont, i)
}
// Checks whether the priority queue is empty.
func (p *Prque) Empty() bool {
return p.cont.Len() == 0
}
// Returns the number of element in the priority queue.
func (p *Prque) Size() int {
return p.cont.Len()
}
// Clears the contents of the priority queue.
func (p *Prque) Reset() {
*p = *New(p.cont.setIndex)
}