Deferred closure execution within a loop

deferrals.go

package main

import (
	"fmt"
	"time"
)

func increment(val *int) {
	defer func() {
		fmt.Println(time.Now(), ": Pre-increment: ", *val)
		*val++
		fmt.Println(time.Now(), ": Post-increment: ", *val)
	}()
}

func main() {
	j := 1

	for i := 0; i < 4; i++ {
		increment(&j)
	}

	fmt.Println(time.Now(), ": final j: ", j)
}

/*
============
OUTPUT:
============

$ go run deferral.go
2015-03-31 10:26:06.110453248 -0600 MDT : Pre-increment:  1
2015-03-31 10:26:06.110682894 -0600 MDT : Post-increment:  2
2015-03-31 10:26:06.110690739 -0600 MDT : Pre-increment:  2
2015-03-31 10:26:06.110693545 -0600 MDT : Post-increment:  3
2015-03-31 10:26:06.110695858 -0600 MDT : Pre-increment:  3
2015-03-31 10:26:06.110698067 -0600 MDT : Post-increment:  4
2015-03-31 10:26:06.110700312 -0600 MDT : Pre-increment:  4
2015-03-31 10:26:06.110702463 -0600 MDT : Post-increment:  5
2015-03-31 10:26:06.110704647 -0600 MDT : final j:  5
*/