1 files changed, 47 insertions, 0 deletions
diff --git a/third_party/rust/clap/examples/derive_ref/custom-bool.md b/third_party/rust/clap/examples/derive_ref/custom-bool.md
new file mode 100644
index 0000000000..2769f20e8f
--- /dev/null
+++ b/third_party/rust/clap/examples/derive_ref/custom-bool.md
@@ -0,0 +1,47 @@
+*Jump to [source](custom-bool.rs)*
+
+Example of overriding the magic `bool` behavior
+
+```console
+$ custom-bool --help
+clap [..]
+A simple to use, efficient, and full-featured Command Line Argument Parser
+
+USAGE:
+    custom-bool[EXE] [OPTIONS] --foo <FOO> <BOOM>
+
+ARGS:
+    <BOOM>    
+
+OPTIONS:
+        --bar <BAR>    [default: false]
+        --foo <FOO>    
+    -h, --help         Print help information
+    -V, --version      Print version information
+
+$ custom-bool
+? failed
+error: The following required arguments were not provided:
+    --foo <FOO>
+    <BOOM>
+
+USAGE:
+    custom-bool[EXE] [OPTIONS] --foo <FOO> <BOOM>
+
+For more information try --help
+
+$ custom-bool --foo true false
+[examples/derive_ref/custom-bool.rs:31] opt = Opt {
+    foo: true,
+    bar: false,
+    boom: false,
+}
+
+$ custom-bool --foo true --bar true false
+[examples/derive_ref/custom-bool.rs:31] opt = Opt {
+    foo: true,
+    bar: true,
+    boom: false,
+}
+
+```