Channels

• A means of allowing communication to and from a GoRoutine
• Channels can be buffered, or unbuffered
• Once you're done with a channel, you must close it
• Channels typically only accept a given type or interface
• When we caopy channel or pass one as an argument to function, we are copying a reference,s o caller & callee refer to same data structure.

ch = make(chan int)    // unbuffered channel of int
ch = make(chan int, 3) // buffered channel with capacity 3

Channel Operations

• Channel has 3 operations. send, recieve & close.

ch <- x   // send x to channel ch
x = <- ch // receive value in x from channel ch
<-ch      // receiving from channel ch but value is discarded.
close(ch) // close channel ch

• attempt to send values to closed channel will result in panic.
• attempt to read from closed channel retuns zero value of channel's element type.

Unbuffered channels

• send/recieve on unbuffered channel blocks sending/recieving goroutine until another goroutine executes a corresponding receive/send on same channel.
• Communication over an unbuffered channel causes the sending and recieving goroutines to synchronize. also called synchronous channels.