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course/13-channels/exercises/7-select/readme.md

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+# Select
+
+Sometimes we have a single goroutine listening to multiple channels and want to process data in the order it comes through each channel.
+
+A `select` statement is used to listen to multiple channels at the same time. It is similar to a `switch` statement but for channels.
+
+```go
+select {
+  case i, ok := <- chInts:
+    fmt.Println(i)
+  case s, ok := <- chStrings:
+    fmt.Println(s)
+}
+```
+
+The first channel with a value ready to be received will fire and its body will execute. If multiple channels are ready at the same time one is chosen randomly. The `ok` variable in the example above refers to whether or not the channel has been closed by the sender yet.
+
+## Assignment
+
+Complete the `logMessages` function.
+
+Use an infinite `for` loop and a select statement to log the emails and sms messages as they come in order across the two channels. Add a condition to `return` from the function when *one* of the two channels closes, whichever is first.
+
+Use the `logSms` and `logEmail` functions to log the messages.