concurrency in golang

concurrency.go

package main

import (
	"sync"
	"net/http"
)

func example_function(){
	// function to be run concurrently
}

func main(){
	var wg sync.WaitGroup // WaitGroups allow your program to wait unitl all goroutines have finished their work
	max_procs := make(chan bool, 50) // it's a chnnael, if you try to add more than 50 bool values to it the program will stop executing unless you remove an item from it
	for _, item := range items { // iterate over items
		go func(item string){ // "go" statement makes a func call to be called async-ly, see line 22 next
			wg.Add(1) // add one item to WaitGroup
			max_procs<-true // add one item to max_procs channel, if it's the 51th item, the program will pause here, unless you remove some items from max_procs channel
			example_function(item) // call your example_function, do your stuff, add more lines here to process the result if you need to
			defer wg.Done() // mark this item as done in WaitGroup
			<-max_procs // remove one item from max_procs, hence allow more items to be added in
		}(item) // you know what it does
	}
	wg.Wait() // wait (i.e. pause execution) until all the items in the wait group are done
}