Implement TryFrom<&[T]> for Vec<T, N>

There already is the Vec::from_slice method that does the same, but
implementing the TryFrom trait makes it easier to write code that works
both with heapless::Vec and std::vec::Vec.

Author: robinkrahl

src/vec.rs

@@ -1,4 +1,7 @@
-use core::{cmp::Ordering, fmt, hash, iter::FromIterator, mem::MaybeUninit, ops, ptr, slice};
+use core::{
+    cmp::Ordering, convert::TryFrom, fmt, hash, iter::FromIterator, mem::MaybeUninit, ops, ptr,
+    slice,
+};
 use hash32;
 
 /// A fixed capacity [`Vec`](https://doc.rust-lang.org/std/vec/struct.Vec.html)
@@ -569,6 +572,14 @@ impl<T, const N: usize> Drop for Vec<T, N> {
     }
 }
 
+impl<'a, T: Clone, const N: usize> TryFrom<&'a [T]> for Vec<T, N> {
+    type Error = ();
+
+    fn try_from(slice: &'a [T]) -> Result<Self, Self::Error> {
+        Vec::from_slice(slice)
+    }
+}
+
 impl<T, const N: usize> Extend<T> for Vec<T, N> {
     fn extend<I>(&mut self, iter: I)
     where