Added try into for DanceRole

src/dance_info.rs

@@ -21,6 +21,28 @@ impl DanceRole {
     }
 }
 
+#[derive(Debug)]
+pub struct ParseDanceRoleError;
+
+impl std::fmt::Display for ParseDanceRoleError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "failed to parse DanceRole")
+    }
+}
+impl std::error::Error for ParseDanceRoleError {}
+
+impl TryFrom<&str> for DanceRole {
+    type Error = ParseDanceRoleError;
+
+    fn try_from(value: &str) -> Result<Self, Self::Error> {
+        match value.to_lowercase().as_str() {
+            "leader" => Ok(DanceRole::Leader),
+            "follower" => Ok(DanceRole::Follower),
+            _ => Err(ParseDanceRoleError),
+        }
+    }
+}
+
 #[derive(serde::Deserialize, Debug, PartialEq, Eq)]
 pub enum DanceRank {
     Newcomer,