Extract Sift{Error, Result} from pure BinaryHeap

src/backing/containers/mod.rs

@@ -1,5 +1,7 @@
 mod pair;
 mod py_item;
+mod sift_result;
 
 pub use pair::Pair;
 pub use py_item::PyItem;
+pub use sift_result::{SiftError, SiftResult};

src/backing/containers/sift_result.rs

@@ -0,0 +1,26 @@
+use std::fmt::{Display, Formatter, Result as fmtResult};
+
+/// Indicates why a sift failed
+#[derive(Debug, Clone)]
+pub struct SiftError {
+    /// The index that couldn't be sifted
+    index: usize,
+    /// The length of the array
+    len: usize,
+}
+
+impl SiftError {
+    /// Instantiates a `SiftError`
+    pub fn new(index: usize, len: usize) -> Self {
+        Self { index, len }
+    }
+}
+
+impl Display for SiftError {
+    fn fmt(&self, f: &mut Formatter) -> fmtResult {
+        write!(f, "Could not sift index {} of {}", self.index, self.len)
+    }
+}
+
+/// Whether a sift operation succeeded
+pub type SiftResult = Result<(), SiftError>;

src/backing/pure/binary_heap.rs

@@ -1,32 +1,7 @@
-use std::fmt;
+use crate::backing::containers::{SiftError, SiftResult};
 
 use super::PureBacking;
 
-/// Indicates why a sift failed
-#[derive(Debug, Clone)]
-struct SiftError {
-    /// The index that couldn't be sifted
-    index: usize,
-    /// The length of the array
-    len: usize,
-}
-
-impl SiftError {
-    /// Instantiates a `SiftError`
-    fn new(index: usize, len: usize) -> Self {
-        Self { index, len }
-    }
-}
-
-impl fmt::Display for SiftError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "Could not sift index {} of {}", self.index, self.len)
-    }
-}
-
-/// Whether a sift operation succeeded
-type SiftResult = Result<(), SiftError>;
-
 /// A binary min-heap backed by an array
 #[derive(Debug)]
 pub struct BinaryHeap<T: PartialOrd + Clone + Send + Sync> {