Merge pull request #5 from WaDelma/master

Added Debug implementations to UnificationTable.

Author: nikomatsakis

src/snapshot_vec.rs

@@ -21,9 +21,11 @@
 
 use self::UndoLog::*;
 
+use std::fmt;
 use std::mem;
 use std::ops;
 
+#[derive(Debug)]
 pub enum UndoLog<D: SnapshotVecDelegate> {
     /// Indicates where a snapshot started.
     OpenSnapshot,
@@ -46,6 +48,20 @@ pub struct SnapshotVec<D: SnapshotVecDelegate> {
     undo_log: Vec<UndoLog<D>>,
 }
 
+impl<D> fmt::Debug for SnapshotVec<D>
+    where D: SnapshotVecDelegate,
+          D: fmt::Debug,
+          D::Undo: fmt::Debug,
+          D::Value: fmt::Debug
+{
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.debug_struct("SnapshotVec")
+            .field("values", &self.values)
+            .field("undo_log", &self.undo_log)
+            .finish()
+    }
+}
+
 // Snapshots are tokens that should be created/consumed linearly.
 pub struct Snapshot {
     // Length of the undo log at the time the snapshot was taken.

src/unify/backing_vec.rs

@@ -39,7 +39,7 @@ pub trait UnificationStore: ops::Index<usize, Output = VarValue<Key<Self>>> + Cl
 
 /// Backing store for an in-place unification table.
 /// Not typically used directly.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct InPlace<K: UnifyKey> {
     values: sv::SnapshotVec<Delegate<K>>
 }
@@ -96,7 +96,7 @@ impl<K> ops::Index<usize> for InPlace<K>
     }
 }
 
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 struct Delegate<K>(PhantomData<K>);
 
 impl<K: UnifyKey> sv::SnapshotVecDelegate for Delegate<K> {
@@ -107,7 +107,7 @@ impl<K: UnifyKey> sv::SnapshotVecDelegate for Delegate<K> {
 }
 
 #[cfg(feature = "persistent")]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct Persistent<K: UnifyKey> {
     values: DVec<VarValue<K>>
 }

src/unify/mod.rs

@@ -176,7 +176,7 @@ pub struct VarValue<K: UnifyKey> { // FIXME pub
 ///     cloning the table is an O(1) operation.
 ///   - This implies that ordinary operations are quite a bit slower though.
 ///   - Requires the `persistent` feature be selected in your Cargo.toml file.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct UnificationTable<S: UnificationStore> {
     /// Indicates the current value of each key.
     values: S,