added example file of writing an error struct/method combo

errors/errors.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+type SMBError struct {
+	What string
+	When time.Time
+}
+
+// the receiver and that which is returned from generate_error must match 
+// types. You may change this to an SMBError pointer recevier, or change the 
+// return from generate_error to be an address.
+func (e SMBError) Error() string {
+	return fmt.Sprintf("%v at %v", e.What, e.When)
+}
+
+func generate_error() error {
+	return SMBError{
+		"Here is a silly error",
+		time.Now(),
+	}
+}
+
+func main() {
+	if err := generate_error(); err != nil {
+		fmt.Println(err)
+	}
+}