Merge pull request #46 from Zoxc/has_cap

Add `has_capacity` as a proxy for `is_singleton`

Author: Gankra

src/lib.rs

@@ -666,6 +666,11 @@ impl<T> ThinVec<T> {
         self.header().cap()
     }
 
+    /// Returns `true` if the vector has the capacity to hold any element.
+    pub fn has_capacity(&self) -> bool {
+        !self.is_singleton()
+    }
+
     /// Forces the length of the vector to `new_len`.
     ///
     /// This is a low-level operation that maintains none of the normal