shuffle user::lookup around so i can fold lookup_ids and lookup_names in

examples/reciprocal.rs

@@ -24,7 +24,7 @@ fn main() {
 
     println!("{} accounts that you follow follow you back.", reciprocals.len());
 
-    for user in user::lookup_ids(&reciprocals, &config.con_token, &config.access_token).unwrap().response {
+    for user in user::lookup(&reciprocals, &config.con_token, &config.access_token).unwrap().response {
         println!("{} (@{})", user.name, user.screen_name);
     }
 }

src/common/mod.rs

@@ -32,6 +32,7 @@ pub fn add_name_param<'a>(list: &mut ParamList<'a>, id: &UserID<'a>) -> Option<C
 }
 
 ///Convenience enum to generalize between referring to an account by numeric ID or by screen name.
+#[derive(Debug, Clone)]
 pub enum UserID<'a> {
     ///Referring via the account's numeric ID.
     ID(i64),
@@ -45,6 +46,12 @@ impl<'a> From<i64> for UserID<'a> {
     }
 }
 
+impl<'a> From<&'a i64> for UserID<'a> {
+    fn from(id: &'a i64) -> UserID<'a> {
+        UserID::ID(*id)
+    }
+}
+
 impl<'a> From<&'a str> for UserID<'a> {
     fn from(name: &'a str) -> UserID<'a> {
         UserID::ScreenName(name)
@@ -56,3 +63,9 @@ impl<'a> From<&'a String> for UserID<'a> {
         UserID::ScreenName(name.as_str())
     }
 }
+
+impl<'a> From<&'a UserID<'a>> for UserID<'a> {
+    fn from(id: &'a UserID<'a>) -> UserID<'a> {
+        id.clone()
+    }
+}

src/user/mod.rs

@@ -64,6 +64,7 @@ pub use user::structs::*;
 //---Groups of users---
 
 ///Lookup a set of Twitter users by their numerical ID.
+#[deprecated(note = "you can call lookup with &[i64] now")]
 pub fn lookup_ids(ids: &[i64], con_token: &auth::Token, access_token: &auth::Token)
     -> Result<Response<Vec<TwitterUser>>, error::Error>
 {
@@ -77,6 +78,7 @@ pub fn lookup_ids(ids: &[i64], con_token: &auth::Token, access_token: &auth::Tok
 }
 
 ///Lookup a set of Twitter users by their screen name.
+#[deprecated(note = "you can call lookup with &[&str] and &[String] now")]
 pub fn lookup_names<S: Borrow<str>>(names: &[S], con_token: &auth::Token, access_token: &auth::Token)
     -> Result<Response<Vec<TwitterUser>>, error::Error>
 {
@@ -90,19 +92,20 @@ pub fn lookup_names<S: Borrow<str>>(names: &[S], con_token: &auth::Token, access
 }
 
 ///Lookup a set of Twitter users by both ID and screen name, as applicable.
-pub fn lookup(accts: &[UserID], con_token: &auth::Token, access_token: &auth::Token)
+pub fn lookup<'a, T: 'a>(accts: &'a [T], con_token: &auth::Token, access_token: &auth::Token)
     -> Result<Response<Vec<TwitterUser>>, error::Error>
+    where &'a T: Into<UserID<'a>>
 {
     let mut params = HashMap::new();
     let id_param = accts.iter()
-                        .filter_map(|x| match *x {
+                        .filter_map(|x| match x.into() {
                             UserID::ID(id) => Some(id.to_string()),
                             _ => None,
                         })
                         .collect::<Vec<_>>()
                         .join(",");
     let name_param = accts.iter()
-                          .filter_map(|x| match *x {
+                          .filter_map(|x| match x.into() {
                               UserID::ScreenName(name) => Some(name),
                               _ => None,
                           })