Remove the Deref implementation for MatrixRef.

Fix #380.

CHANGELOG.md

@@ -35,6 +35,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
   * Implement `Extend<Matrix<...>>` for matrices with dynamic storage. This will concatenate the columns of both matrices.
   * Implement `Into<Vec>` for the `MatrixVec` storage.
   * Implement `Hash` for all matrices.
+  * Add a `.len()` method to retrieve the size of a `MatrixVec`.
 
 ### Modified
   * The orthographic projection no longer require that `bottom < top`, that `left < right`, and that `znear < zfar`. The
@@ -47,6 +48,9 @@ This project adheres to [Semantic Versioning](http://semver.org/).
     This is for the case of `Unit`, `Transform`, `Orthographic3`, `Perspective3`, `Rotation`.
   * Deprecate several functions at the root of the crate (replaced by methods).
 
+### Removed
+    * Remove the `Deref` impl for `MatrixVec` as it could cause hard-to-understand compilation errors.
+
 ### nalgebra-glm
   * Add several alternative projection computations, e.g., `ortho_lh`, `ortho_lh_no`, `perspective_lh`, etc.
   * Add features matching those of nalgebra, in particular: `serde-serialize`, `abmonation-serialize`, std` (enabled by default).

src/base/vec_storage.rs

@@ -1,6 +1,5 @@
 #[cfg(feature = "abomonation-serialize")]
 use std::io::{Result as IOResult, Write};
-use std::ops::Deref;
 
 #[cfg(all(feature = "alloc", not(feature = "std")))]
 use alloc::vec::Vec;
@@ -81,14 +80,11 @@ impl<N, R: Dim, C: Dim> VecStorage<N, R, C> {
 
         self.data
     }
-}
-
-impl<N, R: Dim, C: Dim> Deref for VecStorage<N, R, C> {
-    type Target = Vec<N>;
 
+    /// The number of elements on the underlying vector.
     #[inline]
-    fn deref(&self) -> &Self::Target {
-        &self.data
+    pub fn len(&self) -> usize {
+        self.data.len()
     }
 }
 
@@ -145,7 +141,7 @@ where DefaultAllocator: Allocator<N, Dynamic, C, Buffer = Self>
 
     #[inline]
     fn as_slice(&self) -> &[N] {
-        &self[..]
+        &self.data
     }
 }
 
@@ -189,7 +185,7 @@ where DefaultAllocator: Allocator<N, R, Dynamic, Buffer = Self>
 
     #[inline]
     fn as_slice(&self) -> &[N] {
-        &self[..]
+        &self.data
     }
 }