Fix various useless derefs and slicings

4 files changed, 9 insertions, 10 deletions

diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs
index 021c5398a42..66f5520b882 100644
--- a/src/libsyntax/ext/tt/macro_rules.rs
+++ b/src/libsyntax/ext/tt/macro_rules.rs
@@ -119,7 +119,7 @@ fn generic_extension<'cx>(cx: &'cx ExtCtxt,
                 };
                 let mut p = Parser::new(cx.parse_sess(), tts, Some(directory), false);
                 p.root_module_name = cx.current_expansion.module.mod_path.last()
-                    .map(|id| (*id.name.as_str()).to_owned());
+                    .map(|id| id.name.as_str().to_string());
 
                 p.check_unknown_macro_variable();
                 // Let the context choose how to interpret the result.
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 7af432176cf..9d280a413e6 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -818,7 +818,7 @@ pub struct GatedCfg {
 
 impl GatedCfg {
     pub fn gate(cfg: &ast::MetaItem) -> Option<GatedCfg> {
-        let name = &*cfg.name().as_str();
+        let name = cfg.name().as_str();
         GATED_CFGS.iter()
                   .position(|info| info.0 == name)
                   .map(|idx| {
@@ -865,8 +865,7 @@ macro_rules! gate_feature {
 impl<'a> Context<'a> {
     fn check_attribute(&self, attr: &ast::Attribute, is_macro: bool) {
         debug!("check_attribute(attr = {:?})", attr);
-        let name = unwrap_or!(attr.name(), return);
-
+        let name = unwrap_or!(attr.name(), return).as_str();
         for &(n, ty, ref gateage) in BUILTIN_ATTRIBUTES {
             if name == n {
                 if let &Gated(_, ref name, ref desc, ref has_feature) = gateage {
@@ -885,12 +884,12 @@ impl<'a> Context<'a> {
                 return;
             }
         }
-        if name.as_str().starts_with("rustc_") {
+        if name.starts_with("rustc_") {
             gate_feature!(self, rustc_attrs, attr.span,
                           "unless otherwise specified, attributes \
                            with the prefix `rustc_` \
                            are reserved for internal compiler diagnostics");
-        } else if name.as_str().starts_with("derive_") {
+        } else if name.starts_with("derive_") {
             gate_feature!(self, custom_derive, attr.span, EXPLAIN_DERIVE_UNDERSCORE);
         } else if !attr::is_known(attr) {
             // Only run the custom attribute lint during regular
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 649e9059934..43a9d8c5f78 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -5151,15 +5151,15 @@ impl<'a> Parser<'a> {
 
     fn push_directory(&mut self, id: Ident, attrs: &[Attribute]) {
         if let Some(path) = attr::first_attr_value_str_by_name(attrs, "path") {
-            self.directory.path.push(&*path.as_str());
+            self.directory.path.push(&path.as_str());
             self.directory.ownership = DirectoryOwnership::Owned;
         } else {
-            self.directory.path.push(&*id.name.as_str());
+            self.directory.path.push(&id.name.as_str());
         }
     }
 
     pub fn submod_path_from_attr(attrs: &[ast::Attribute], dir_path: &Path) -> Option<PathBuf> {
-        attr::first_attr_value_str_by_name(attrs, "path").map(|d| dir_path.join(&*d.as_str()))
+        attr::first_attr_value_str_by_name(attrs, "path").map(|d| dir_path.join(&d.as_str()))
     }
 
     /// Returns either a path to a module, or .
diff --git a/src/libsyntax/test.rs b/src/libsyntax/test.rs
index e052d2cda3a..6fb6db9ca02 100644
--- a/src/libsyntax/test.rs
+++ b/src/libsyntax/test.rs
@@ -616,7 +616,7 @@ fn mk_tests(cx: &TestCtxt) -> P<ast::Item> {
 
 fn is_test_crate(krate: &ast::Crate) -> bool {
     match attr::find_crate_name(&krate.attrs) {
-        Some(s) if "test" == &*s.as_str() => true,
+        Some(s) if "test" == s.as_str() => true,
         _ => false
     }
 }