examples/tcp_echo_server: cleanup, use defer{}

examples/tcp_echo_server.v

@@ -1,23 +1,29 @@
 import net
-
 // This file shows how a basic TCP echo server can be implemented using
 // the `net` module. You can connect to the server by using netcat
 // or telnet, in separate shells, for example:
 // `nc 127.0.0.1 12345`
 // `telnet 127.0.0.1 12345`
-
 fn handle_connection(con net.Socket) {
-	if _ := con.send_string("Welcome to V's TCP Echo server.\n") {
+	eprintln('new client connected')
+	defer {
+		eprintln('closing connection: $con')
+		con.close() or { }
+	}
+	con.send_string("Welcome to V's TCP Echo server.\n") or {
+		return
+	}
 	for {
 		line := con.read_line()
-			if line.len == 0 { break }
-			eprintln('received line: ' + line.trim_space())
-			con.send_string(line) or { break }
-		}
-	}
-	con.close() or {}
+		if line.len == 0 {
 			return
 		}
+		eprintln('received line: ' + line.trim_space())
+		con.send_string(line) or {
+			return
+		}
+	}
+}
 
 fn main() {
 	server_port := 12345