1 files changed, 29 insertions, 0 deletions
diff --git a/clap/examples/09_auto_version.rs b/clap/examples/09_auto_version.rs
new file mode 100644
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--- /dev/null
+++ b/clap/examples/09_auto_version.rs
@@ -0,0 +1,29 @@
+#[macro_use]
+extern crate clap;
+
+use clap::App;
+
+fn main() {
+    // You can have clap pull the application version directly from your Cargo.toml starting with
+    // clap v0.4.14 on crates.io (or master#a81f915 on github). Using Rust's env! macro like this:
+    //
+    // let version = format!("{}.{}.{}{}",
+    //                  env!("CARGO_PKG_VERSION_MAJOR"),
+    //                  env!("CARGO_PKG_VERSION_MINOR"),
+    //                  env!("CARGO_PKG_VERSION_PATCH"),
+    //                  option_env!("CARGO_PKG_VERSION_PRE").unwrap_or(""));
+    //
+    // Starting from v0.6.6 on crates.io you can also use the crate_version!() macro instead of
+    // manually using the env!() macros. Under the hood, the macro uses this exact method to get
+    // the version.
+    //
+    // Thanks to https://github.com/jhelwig for pointing this out
+    App::new("myapp")
+        .about("does awesome things")
+       // use crate_version! to pull the version number
+       .version(crate_version!())
+       .get_matches();
+
+    // running this app with the -V or --version will display whatever version is in your
+    // Cargo.toml, the default being: myapp 0.0.1
+}