1 files changed, 39 insertions, 0 deletions
diff --git a/third_party/rust/fixedbitset/src/range.rs b/third_party/rust/fixedbitset/src/range.rs
new file mode 100644
index 0000000000..aaa48961b5
--- /dev/null
+++ b/third_party/rust/fixedbitset/src/range.rs
@@ -0,0 +1,39 @@
+use std::ops::{
+    RangeFull,
+    RangeFrom,
+    RangeTo,
+    Range,
+};
+
+// Taken from https://github.com/bluss/odds/blob/master/src/range.rs.
+
+/// **IndexRange** is implemented by Rust's built-in range types, produced
+/// by range syntax like `..`, `a..`, `..b` or `c..d`.
+pub trait IndexRange<T=usize> {
+    #[inline]
+    /// Start index (inclusive)
+    fn start(&self) -> Option<T> { None }
+    #[inline]
+    /// End index (exclusive)
+    fn end(&self) -> Option<T> { None }
+}
+
+
+impl<T> IndexRange<T> for RangeFull {}
+
+impl<T: Copy> IndexRange<T> for RangeFrom<T> {
+    #[inline]
+    fn start(&self) -> Option<T> { Some(self.start) }
+}
+
+impl<T: Copy> IndexRange<T> for RangeTo<T> {
+    #[inline]
+    fn end(&self) -> Option<T> { Some(self.end) }
+}
+
+impl<T: Copy> IndexRange<T> for Range<T> {
+    #[inline]
+    fn start(&self) -> Option<T> { Some(self.start) }
+    #[inline]
+    fn end(&self) -> Option<T> { Some(self.end) }
+}