EncodeArguments trait doesn't allocate anymore.

Author: SSheldon

src/declare.rs

@@ -80,12 +80,6 @@ pub trait MethodImplementation {
     fn imp_for(self, sel: Sel) -> Result<Imp, UnequalArgsError>;
 }
 
-macro_rules! count_idents {
-    () => (0);
-    ($a:ident) => (1);
-    ($a:ident, $($b:ident),+) => (1 + count_idents!($($b),*));
-}
-
 macro_rules! method_decl_impl {
     (-$s:ident, $r:ident, $f:ty, $($t:ident),*) => (
         impl<$s, $r $(, $t)*> MethodImplementation for $f
@@ -128,7 +122,7 @@ method_decl_impl!(A, B, C, D, E, F, G, H, I, J, K, L);
 
 fn method_type_encoding<F>() -> CString where F: MethodImplementation {
     let mut types = F::Ret::encode().as_str().to_owned();
-    types.extend(F::Args::encodings().iter().map(|e| e.as_str()));
+    types.extend(F::Args::encodings().as_ref().iter().map(|e| e.as_str()));
     CString::new(types).unwrap()
 }
 

src/macros.rs

@@ -102,6 +102,12 @@ macro_rules! objc_try {
     ($b:block) => ($b)
 }
 
+macro_rules! count_idents {
+    () => (0);
+    ($a:ident) => (1);
+    ($a:ident, $($b:ident),+) => (1 + count_idents!($($b),*));
+}
+
 macro_rules! encode {
     () => ("");
     (i8 $($x:tt)*) => (concat!("c", encode!($($x)*)));

src/verify.rs

@@ -4,18 +4,22 @@ use runtime::{Class, Object, Sel};
 use {Encode, Encoding};
 
 pub trait EncodeArguments {
-    fn encodings() -> Box<[Encoding]>;
+    type Encs: AsRef<[Encoding]>;
+
+    fn encodings() -> Self::Encs;
 }
 
 macro_rules! encode_args_impl {
     ($($t:ident),*) => (
         impl<$($t: Encode),*> EncodeArguments for ($($t,)*) {
-            fn encodings() -> Box<[Encoding]> {
-                Box::new([
+            type Encs = [Encoding; 2 + count_idents!($($t),*)];
+
+            fn encodings() -> Self::Encs {
+                [
                     <*mut Object>::encode(),
                     Sel::encode(),
                     $($t::encode()),*
-                ])
+                ]
             }
         }
     );
@@ -51,6 +55,7 @@ pub fn verify_message_signature<A, R>(cls: &Class, sel: Sel) -> Result<(), Strin
     }
 
     let args = A::encodings();
+    let args = args.as_ref();
     let count = args.len();
     let expected_count = method.arguments_count();
     if count != expected_count {