command line argument parsing

Cargo.toml

@@ -7,3 +7,5 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+docopt = "1.1.0"
+serde = "1.0.91"

src/main.rs

@@ -1,3 +1,37 @@
+use docopt::Docopt;
+use serde::Deserialize;
+
+static USAGE: &'static str = "
+foil
+
+Usage:
+  foil set [--db=<db>]
+  foil get [--db=<db>]
+  foil list [--db=<db>]
+  foil generate <spec>
+  foil (-h | --help)
+
+Options:
+  --db=<db>     The path to the sqlite database [default: db.sqlite3].
+  -h --help     Show this screen.
+  --version     Show version.
+";
+
+#[derive(Debug, Deserialize)]
+struct Args {
+    cmd_set: bool,
+    cmd_get: bool,
+    cmd_list: bool,
+    cmd_generate: bool,
+    flag_db: Option<String>,
+    arg_spec: Option<String>,
+}
+
 fn main() {
     println!("Hello, world!");
+    let args: Args = Docopt::new(USAGE)
+        .and_then(|dopt| dopt.deserialize())
+        .unwrap_or_else(|e| e.exit());
+    println!("{:?}", args);
+
 }