From 5943b1ad42eb1faeef8363f7c0078888d0589f7f Mon Sep 17 00:00:00 2001
From: Marco Molteni <marco.molteni@mailbox.org>
Date: Thu, 23 Jan 2020 18:16:28 +0100
Subject: [PATCH] README: how to terminate a program when no subcommands are
 specified

Fixes #103
---
 README.md | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/README.md b/README.md
index 037d8d9..3a77953 100644
--- a/README.md
+++ b/README.md
@@ -442,6 +442,17 @@ Some additional rules apply when working with subcommands:
 * The `subcommand` tag can only be used with fields that are pointers to structs
 * Any struct that contains a subcommand must not contain any positionals
 
+This package allows to have a program that accepts subcommands, but also does something else
+when no subcommands are specified.
+If on the other hand you want the program to terminate when no subcommands are specified,
+the recommended way is:
+
+```go
+p := arg.MustParse(&args)
+if p.Subcommand() == nil {
+    p.Fail("missing subcommand")
+}
+```
 
 ### API Documentation