How do I (succinctly) remove the first element from a slice in Go?
If you want a ring buffer or FIFO structure then using a slice as in @Everton's answer will cause garbage collection problems as the underlying array may grow indefinitely.
The easiest way to do this in go, provided you don't mind having a limited size, is to use a channel which is also safe for concurrent access. This is such a common idiom in go that you wouldn't usually bother wrapping it in a type like the below.
Eg (Playground)
package main
import "fmt"
type Queue struct {
elements chan interface{}
}
func NewQueue(size int) *Queue {
return &Queue{
elements: make(chan interface{}, size),
}
}
func (queue *Queue) Push(element interface{}) {
select {
case queue.elements <- element:
default:
panic("Queue full")
}
}
func (queue *Queue) Pop() interface{} {
select {
case e := <-queue.elements:
return e
default:
panic("Queue empty")
}
return nil
}
func main() {
q := NewQueue(128)
q.Push(1)
q.Push(2)
q.Push(3)
fmt.Printf("Pop %d\n", q.Pop())
fmt.Printf("Pop %d\n", q.Pop())
fmt.Printf("Pop %d\n", q.Pop())
fmt.Printf("Pop %d\n", q.Pop())
}
Did you try these?
Pop from queue
x, a = a[0], a[1:]
Pop from stack
x, a = a[len(a)-1], a[:len(a)-1]
Push
a = append(a, x)
From: https://code.google.com/p/go-wiki/wiki/SliceTricks