GO by example, part 5

5-go-by-example/45-recover.go

@@ -0,0 +1,27 @@
+package main
+
+import "fmt"
+
+// this function panics
+func mayPanic() {
+	panic("a problem")
+}
+
+// it is possible to recover from a panic, by using the recover built-in function
+func main() {
+
+	// recover must be called within a deferred function
+	// when the enclosing function panics, the defer will activate and a recover call within it will catch the panic
+	defer func() {
+		if r := recover(); r != nil {
+			// the return value of recover is the error raised in the call to panic
+			fmt.Println("Recovered. Error:\n", r)
+		}
+	}()
+
+	mayPanic()
+
+	// this code will not run, because mayPanic panics
+	// the execution of main stops at the point of the panic and resumes in the deferred closure
+	fmt.Println("After mayPanic()")
+}