Import structopt-0.3.14
Change-Id: I03e7eaf9f442092701ce3175cb78c8ea2237f616
diff --git a/examples/env.rs b/examples/env.rs
new file mode 100644
index 0000000..0477089
--- /dev/null
+++ b/examples/env.rs
@@ -0,0 +1,26 @@
+//! How to use environment variable fallback an how it
+//! interacts with `default_value`.
+
+use structopt::StructOpt;
+
+/// Example for allowing to specify options via environment variables.
+#[derive(StructOpt, Debug)]
+#[structopt(name = "env")]
+struct Opt {
+ // Use `env` to enable specifying the option with an environment
+ // variable. Command line arguments take precedence over env.
+ /// URL for the API server
+ #[structopt(long, env = "API_URL")]
+ api_url: String,
+
+ // The default value is used if neither argument nor environment
+ // variable is specified.
+ /// Number of retries
+ #[structopt(long, env = "RETRIES", default_value = "5")]
+ retries: u32,
+}
+
+fn main() {
+ let opt = Opt::from_args();
+ println!("{:#?}", opt);
+}