Changed some &str-parametres to impl AsRef<str>. (#652)

Some API-functions are able to benefit from greater flexibility if `impl AsRef<str>` is expected rather than just `&str`.

src/client/mod.rs

@@ -340,17 +340,17 @@ impl Client {
     /// #    try_main().unwrap();
     /// # }
     /// ```
-    pub fn new<H>(token: &str, handler: H) -> Result<Self>
+    pub fn new<H>(token: impl AsRef<str>, handler: H) -> Result<Self>
         where H: EventHandler + Send + Sync + 'static {
 
-        Self::new_with_handlers(token, Some(handler), None::<DummyRawEventHandler>)
+        Self::new_with_handlers(token.as_ref(), Some(handler), None::<DummyRawEventHandler>)
     }
     /// Creates a client with an optional Handler. If you pass `None`, events are never parsed, but
     /// they can be received by registering a RawHandler.
-    pub fn new_with_handlers<H, RH>(token: &str, handler: Option<H>, raw_handler: Option<RH>) -> Result<Self>
+    pub fn new_with_handlers<H, RH>(token: impl AsRef<str>, handler: Option<H>, raw_handler: Option<RH>) -> Result<Self>
         where H: EventHandler + Send + Sync + 'static,
               RH: RawEventHandler + Send + Sync + 'static {
-        let token = token.trim();
+        let token = token.as_ref().trim();
 
         let token = if token.starts_with("Bot ") {
             token.to_string()
@@ -452,9 +452,9 @@ impl Client {
     /// # }
     /// ```
     #[cfg(all(feature = "cache", feature = "http"))]
-    pub fn new_with_cache_update_timeout<H>(token: &str, handler: H, duration: Option<Duration>) -> Result<Self>
+    pub fn new_with_cache_update_timeout<H>(token: impl AsRef<str>, handler: H, duration: Option<Duration>) -> Result<Self>
         where H: EventHandler + Send + Sync + 'static {
-        let token = token.trim();
+        let token = token.as_ref().trim();
 
         let token = if token.starts_with("Bot ") {
             token.to_string()
@@ -1047,7 +1047,9 @@ impl Client {
 /// The type of failure is not specified.
 ///
 /// [`ClientError::InvalidToken`]: enum.ClientError.html#variant.InvalidToken
-pub fn validate_token(token: &str) -> Result<()> {
+pub fn validate_token(token: impl AsRef<str>) -> Result<()> {
+    let token = token.as_ref();
+
     if token.is_empty() {
         return Err(Error::Client(ClientError::InvalidToken));
     }

src/model/channel/message.rs

@@ -463,7 +463,9 @@ impl Message {
     /// [`ModelError::MessageTooLong`]: ../error/enum.Error.html#variant.MessageTooLong
     /// [Send Messages]: ../permissions/struct.Permissions.html#associatedconstant.SEND_MESSAGES
     #[cfg(feature = "client")]
-    pub fn reply(&self, cache_http: impl CacheHttp, content: &str) -> Result<Message> {
+    pub fn reply(&self, cache_http: impl CacheHttp, content: impl AsRef<str>) -> Result<Message> {
+        let content = content.as_ref();
+
         if let Some(length_over) = Message::overflow_length(content) {
             return Err(Error::Model(ModelError::MessageTooLong(length_over)));
         }

src/utils/mod.rs

@@ -135,7 +135,9 @@ pub fn parse_invite(code: &str) -> &str {
 /// ```
 ///
 /// [`User`]: ../model/user/struct.User.html
-pub fn parse_username(mention: &str) -> Option<u64> {
+pub fn parse_username(mention: impl AsRef<str>) -> Option<u64> {
+    let mention = mention.as_ref();
+
     if mention.len() < 4 {
         return None;
     }
@@ -174,7 +176,9 @@ pub fn parse_username(mention: &str) -> Option<u64> {
 /// ```
 ///
 /// [`Role`]: ../model/guild/struct.Role.html
-pub fn parse_role(mention: &str) -> Option<u64> {
+pub fn parse_role(mention: impl AsRef<str>) -> Option<u64> {
+    let mention = mention.as_ref();
+
     if mention.len() < 4 {
         return None;
     }
@@ -211,7 +215,9 @@ pub fn parse_role(mention: &str) -> Option<u64> {
 /// ```
 ///
 /// [`Channel`]: ../model/channel/enum.Channel.html
-pub fn parse_channel(mention: &str) -> Option<u64> {
+pub fn parse_channel(mention: impl AsRef<str>) -> Option<u64> {
+    let mention = mention.as_ref();
+
     if mention.len() < 4 {
         return None;
     }
@@ -237,7 +243,9 @@ pub fn parse_channel(mention: &str) -> Option<u64> {
 /// assert_eq!(parse_mention("<@&137235212097683456>"), Some(137235212097683456));
 /// assert_eq!(parse_mention("<#137234234728251392>"), Some(137234234728251392));
 /// ```
-pub fn parse_mention(mention: &str) -> Option<u64> {
+pub fn parse_mention(mention: impl AsRef<str>) -> Option<u64> {
+    let mention = mention.as_ref();
+
     if mention.starts_with("<@&") {
         parse_role(mention)
     } else if mention.starts_with("<@") || mention.starts_with("<@!") {
@@ -280,7 +288,9 @@ pub fn parse_mention(mention: &str) -> Option<u64> {
 /// ```
 ///
 /// [`Emoji`]: ../model/guild/struct.Emoji.html
-pub fn parse_emoji(mention: &str) -> Option<EmojiIdentifier> {
+pub fn parse_emoji(mention: impl AsRef<str>) -> Option<EmojiIdentifier> {
+    let mention = mention.as_ref();
+
     let len = mention.len();
 
     if len < 6 || len > 56 {
@@ -385,7 +395,8 @@ fn _read_image(path: &Path) -> Result<String> {
 ///
 /// assert_eq!(parse_quotes(command), expected);
 /// ```
-pub fn parse_quotes(s: &str) -> Vec<String> {
+pub fn parse_quotes(s: impl AsRef<str>) -> Vec<String> {
+    let s = s.as_ref();
     let mut args = vec![];
     let mut in_string = false;
     let mut escaping = false;
@@ -784,8 +795,8 @@ fn clean_users(cache: &RwLock<Cache>, s: &mut String, show_discriminator: bool,
 /// [`ContentSafeOptions`]: struct.ContentSafeOptions.html
 /// [`Cache`]: ../cache/struct.Cache.html
 #[cfg(feature = "cache")]
-pub fn content_safe(cache: impl AsRef<CacheRwLock>, s: &str, options: &ContentSafeOptions) -> String {
-    let mut s = s.to_string();
+pub fn content_safe(cache: impl AsRef<CacheRwLock>, s: impl AsRef<str>, options: &ContentSafeOptions) -> String {
+    let mut s = s.as_ref().to_string();
     let cache = cache.as_ref();
 
     if options.clean_role {