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diff --git a/clap/examples/13b_enum_values_manual.rs b/clap/examples/13b_enum_values_manual.rs
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+++ b/clap/examples/13b_enum_values_manual.rs
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+// In the following example we will create an enum with 4 values, assign a positional argument
+// that accepts only one of those values, and use clap to parse the argument.
+//
+// Start with bringing the trait into scope.
+use std::str::FromStr;
+
+// Add clap like normal
+#[macro_use]
+extern crate clap;
+
+use clap::{App, Arg};
+
+// Define your enum
+enum Vals {
+    Foo,
+    Bar,
+    Baz,
+    Qux
+}
+
+// Implement the trait
+impl FromStr for Vals {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "Foo" => Ok(Vals::Foo),
+            "Bar" => Ok(Vals::Bar),
+            "Baz" => Ok(Vals::Baz),
+            "Qux" => Ok(Vals::Qux),
+            _     => Err("no match")
+        }
+    }
+}
+
+fn main() {
+    // Create the application like normal
+    let m = App::new("myapp")
+                    // Use a single positional argument that is required
+                    .arg(Arg::from_usage("<type> 'The type to use'")
+                            // Define the list of possible values
+                            .possible_values(&["Foo", "Bar", "Baz", "Qux"]))
+                    .get_matches();
+
+    let t = value_t!(m, "type", Vals).unwrap_or_else(|e| e.exit());
+
+    // Now we can use our enum like normal.
+    match t {
+        Vals::Foo => println!("Found a Foo"),
+        Vals::Bar => println!("Found a Bar"),
+        Vals::Baz => println!("Found a Baz"),
+        Vals::Qux => println!("Found a Qux")
+    }
+}