{"id":1332,"date":"2021-02-26T08:36:20","date_gmt":"2021-02-26T08:36:20","guid":{"rendered":"https:\/\/blog.samarthya.me\/wps\/?p=1332"},"modified":"2021-02-27T15:49:09","modified_gmt":"2021-02-27T15:49:09","slug":"fun-with-goroutines","status":"publish","type":"post","link":"https:\/\/blog.samarthya.me\/wps\/2021\/02\/26\/fun-with-goroutines\/","title":{"rendered":"Fun with `goroutines`"},"content":{"rendered":"

Channels are way of communication between multiple goroutines<\/code><\/p>\n\n\n

You can declare a channel and the type of content the channel will receive like below.<\/p>\n\n\n\n

var myChannel chan int<\/code><\/pre>\n\n\n\n
The int<\/code> above is the type of data it can receive and the data can be send using<\/p>\n\n\n\n
\/\/ Send 10 through channel\nmyChannel <- 10<\/code><\/pre>\n\n\n\n
\/\/Receive the channel content\nval := <- myChannel<\/code><\/pre>\n\n\n\n
In this blog I will just play out some sample scenarios of sending valid information and waiting for the goroutine<\/code> to sed\/receive the data.<\/p>\n\n\n\n
Send<\/h3>\n\n\n\n
func send<\/code> will send data [1..10]<\/code> to ch<\/code> and sleep ever time it is send<\/p>\n\n\n\n
func send(ch chan int) {\n\tfor i := 0; i < 10; i++ {\n\t\ttime.Sleep(1 * time.Second)\n\t\tch <- i\n\t}\n\tfmt.Println(\" Sender done...\")\n\treturn\n}<\/code><\/pre>\n\n\n\n
Receive<\/h3>\n\n\n\n
func receive<\/code> will receive all the information sent to the channel till the last info.<\/p>\n\n\n\n
func receive(ch chan int) {\n\tvar val int\n\n\tfor {\n\t\tval = <-ch\n\t\tfmt.Printf(\" > %d\\n\", val)\n\t\tif val >= 10 {\n\t\t\tclose(ch)\n\t\t\tdone <- true\n\t\t}\n\t}\n}<\/code><\/pre>\n\n\n\n
Term<\/h3>\n\n\n\n
func term() {\n\tdone <- true\n}<\/code><\/pre>\n\n\n\n
Main<\/h3>\n\n\n\n
Playing out the entry point to call the send and receive<\/p>\n\n\n\n
func main() {\n\tfmt.Println(\" --- Main ---\")\n\tch := make(chan int)\n\n\tgo send(ch)\n\tgo receive(ch)\n\n\t\/\/ wait on done\n\t<-done\n\tfmt.Println(\" Done.. \")\n}<\/code><\/pre>\n\n\n\n
Output<\/h3>\n\n\n\n
 > 0\n > 1\n > 2\n > 3\n > 4\n > 5\n > 6\n > 7\n > 8\n Sender done...\n Closing reciever...\n > 9\n Receiver done...\n Done.. \n<\/code><\/pre>\n\n\n\n
Source repository is available here<\/a>.<\/p>\n\n\n\n
What If?<\/h3>\n\n\n\n
If you try sending a different type to the channel type defined – what shall happen?<\/p>\n\n\n\n
  • Will it throw runtime error?<\/li>
  • Will it ignore?<\/li>
  • Will it throw compile time error?<\/li><\/ul>\n\n\n\n
    Easier to try<\/p><\/blockquote><\/figure>\n\n\n\n
    var done chan bool = make(chan bool)\ndone <- 'a'<\/code><\/pre>\n\n\n\n
    \"\"<\/figure>\n\n\n\n
    It just does throws compile time error<\/p>\n\n\n\n
    # command-line-arguments\nsrc\/main.go:57:7: cannot use 'a' (type untyped rune) as type bool in send<\/code><\/pre>\n\n\n\n
    <\/p>\n","protected":false},"excerpt":{"rendered":"
    Channels are way of communication between multiple goroutines You can declare a channel and the type of content the channel will receive like below. The int above is the type of data it can receive and the data can be send using In this blog I will just play out some sample scenarios of sending […]<\/p>\n","protected":false},"author":2,"featured_media":1334,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"image","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[137],"tags":[165,166,167],"class_list":["post-1332","post","type-post","status-publish","format-image","has-post-thumbnail","hentry","category-golang","tag-channels","tag-concurrency","tag-fun","post_format-post-format-image"],"_links":{"self":[{"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/posts\/1332","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/comments?post=1332"}],"version-history":[{"count":0,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/posts\/1332\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/media\/1334"}],"wp:attachment":[{"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/media?parent=1332"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/categories?post=1332"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.samarthya.me\/wps\/wp-json\/wp\/v2\/tags?post=1332"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}