Add INT4[] support

types/array.rs

@@ -0,0 +1,282 @@
+//! Multi-dimensional arrays with per-dimension specifiable lower bounds
+
+use std::cast;
+use std::vec::VecIterator;
+
+#[deriving(Eq, Clone)]
+pub struct DimensionInfo {
+    len: uint,
+    lower_bound: int,
+}
+
+pub trait Array<T> {
+    fn get_dimension_info<'a>(&'a self) -> &'a [DimensionInfo];
+    fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T>;
+    fn get<'a>(&'a self, idx: int) -> &'a T;
+}
+
+pub trait MutableArray<T> : Array<T> {
+    fn slice_mut<'a>(&'a mut self, idx: int) -> MutArraySlice<'a, T> {
+        MutArraySlice { slice: self.slice(idx) }
+    }
+
+    fn get_mut<'a>(&'a mut self, idx: int) -> &'a mut T {
+        unsafe { cast::transmute_mut(self.get(idx)) }
+    }
+}
+
+trait InternalArray<T> : Array<T> {
+    fn shift_idx(&self, idx: int) -> uint {
+        let shifted_idx = idx - self.get_dimension_info()[0].lower_bound;
+        assert!(shifted_idx >= 0, "Out of bounds array access");
+        shifted_idx as uint
+    }
+
+    fn raw_get<'a>(&'a self, idx: uint, size: uint) -> &'a T;
+}
+
+#[deriving(Eq, Clone)]
+pub struct ArrayBase<T> {
+    priv info: ~[DimensionInfo],
+    priv data: ~[T],
+}
+
+impl<T> ArrayBase<T> {
+    pub fn from_raw(data: ~[T], info: ~[DimensionInfo])
+            -> ArrayBase<T> {
+        assert!(!info.is_empty(), "Cannot create a 0x0 array");
+        assert!(data.len() == info.iter().fold(1, |acc, i| acc * i.len),
+                "Size mismatch");
+        ArrayBase {
+            info: info,
+            data: data,
+        }
+    }
+
+    pub fn from_vec(data: ~[T], lower_bound: int) -> ArrayBase<T> {
+        ArrayBase {
+            info: ~[DimensionInfo {
+                len: data.len(),
+                lower_bound: lower_bound
+            }],
+            data: data
+        }
+    }
+
+    pub fn wrap(&mut self, lower_bound: int) {
+        self.info.unshift(DimensionInfo {
+            len: 1,
+            lower_bound: lower_bound
+        })
+    }
+
+    pub fn push_move(&mut self, other: ArrayBase<T>) {
+        assert!(self.info.len() - 1 == other.info.len(),
+                "Cannot append differently shaped arrays");
+        for (info1, info2) in self.info.iter().skip(1).zip(other.info.iter()) {
+            assert!(info1 == info2, "Cannot append differently shaped arrays");
+        }
+        self.info[0].len += 1;
+        self.data.push_all_move(other.data);
+    }
+
+    pub fn values<'a>(&'a self) -> VecIterator<'a, T> {
+        self.data.iter()
+    }
+}
+
+impl<T> Array<T> for ArrayBase<T> {
+    fn get_dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
+        self.info.as_slice()
+    }
+
+    fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
+        ArraySlice {
+            parent: BaseParent(self),
+            idx: self.shift_idx(idx)
+        }
+    }
+
+    fn get<'a>(&'a self, idx: int) -> &'a T {
+        assert!(self.info.len() == 1,
+                "Attempted to get from a multi-dimensional array");
+        self.raw_get(self.shift_idx(idx), 1)
+    }
+}
+
+impl<T> MutableArray<T> for ArrayBase<T> {}
+
+impl<T> InternalArray<T> for ArrayBase<T> {
+    fn raw_get<'a>(&'a self, idx: uint, _size: uint) -> &'a T {
+        &self.data[idx]
+    }
+}
+
+enum ArrayParent<'parent, T> {
+    SliceParent(&'parent ArraySlice<'parent, T>),
+    BaseParent(&'parent ArrayBase<T>),
+}
+
+pub struct ArraySlice<'parent, T> {
+    priv parent: ArrayParent<'parent, T>,
+    priv idx: uint,
+}
+
+impl<'parent, T> Array<T> for ArraySlice<'parent, T> {
+    fn get_dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
+        let info = match self.parent {
+            SliceParent(p) => p.get_dimension_info(),
+            BaseParent(p) => p.get_dimension_info()
+        };
+        info.slice_from(1)
+    }
+
+    fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
+        ArraySlice {
+            parent: SliceParent(self),
+            idx: self.shift_idx(idx)
+        }
+    }
+
+    fn get<'a>(&'a self, idx: int) -> &'a T {
+        assert!(self.get_dimension_info().len() == 1,
+                "Attempted to get from a multi-dimensional array");
+        self.raw_get(self.shift_idx(idx), 1)
+    }
+}
+
+impl<'parent, T> InternalArray<T> for ArraySlice<'parent, T> {
+    fn raw_get<'a>(&'a self, idx: uint, size: uint) -> &'a T {
+        let size = size * self.get_dimension_info()[0].len;
+        let idx = size * self.idx + idx;
+        match self.parent {
+            SliceParent(p) => p.raw_get(idx, size),
+            BaseParent(p) => p.raw_get(idx, size)
+        }
+    }
+}
+
+pub struct MutArraySlice<'parent, T> {
+    priv slice: ArraySlice<'parent, T>
+}
+
+impl<'parent, T> Array<T> for MutArraySlice<'parent, T> {
+    fn get_dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
+        self.slice.get_dimension_info()
+    }
+
+    fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
+        self.slice.slice(idx)
+    }
+
+    fn get<'a>(&'a self, idx: int) -> &'a T {
+        self.slice.get(idx)
+    }
+}
+
+impl<'parent, T> MutableArray<T> for MutArraySlice<'parent, T> {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_from_vec() {
+        let a = ArrayBase::from_vec(~[0, 1, 2], -1);
+        assert_eq!([DimensionInfo { len: 3, lower_bound: -1 }],
+                   a.get_dimension_info());
+        assert_eq!(&0, a.get(-1));
+        assert_eq!(&1, a.get(0));
+        assert_eq!(&2, a.get(1));
+    }
+
+    #[test]
+    #[should_fail]
+    fn test_get_2d_fail() {
+        let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
+        a.wrap(1);
+        a.get(1);
+    }
+
+    #[test]
+    #[should_fail]
+    fn test_2d_slice_range_fail() {
+        let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
+        a.wrap(1);
+        a.slice(0);
+    }
+
+    #[test]
+    fn test_2d_slice_get() {
+        let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
+        a.wrap(1);
+        let s = a.slice(1);
+        assert_eq!(&0, s.get(-1));
+        assert_eq!(&1, s.get(0));
+        assert_eq!(&2, s.get(1));
+    }
+
+    #[test]
+    #[should_fail]
+    fn test_push_move_wrong_lower_bound() {
+        let mut a = ArrayBase::from_vec(~[1], -1);
+        a.push_move(ArrayBase::from_vec(~[2], 0));
+    }
+
+    #[test]
+    #[should_fail]
+    fn test_push_move_wrong_dims() {
+        let mut a = ArrayBase::from_vec(~[1], -1);
+        a.wrap(1);
+        a.push_move(ArrayBase::from_vec(~[1, 2], -1));
+    }
+
+    #[test]
+    #[should_fail]
+    fn test_push_move_wrong_dim_count() {
+        let mut a = ArrayBase::from_vec(~[1], -1);
+        a.wrap(1);
+        let mut b = ArrayBase::from_vec(~[2], -1);
+        b.wrap(1);
+        a.push_move(b);
+    }
+
+    #[test]
+    fn test_push_move_ok() {
+        let mut a = ArrayBase::from_vec(~[1, 2], 0);
+        a.wrap(0);
+        a.push_move(ArrayBase::from_vec(~[3, 4], 0));
+        let s = a.slice(0);
+        assert_eq!(&1, s.get(0));
+        assert_eq!(&2, s.get(1));
+        let s = a.slice(1);
+        assert_eq!(&3, s.get(0));
+        assert_eq!(&4, s.get(1));
+    }
+
+    #[test]
+    fn test_3d() {
+        let mut a = ArrayBase::from_vec(~[0, 1], 0);
+        a.wrap(0);
+        a.push_move(ArrayBase::from_vec(~[2, 3], 0));
+        a.wrap(0);
+        let mut b = ArrayBase::from_vec(~[4, 5], 0);
+        b.wrap(0);
+        b.push_move(ArrayBase::from_vec(~[6, 7], 0));
+        a.push_move(b);
+        let s1 = a.slice(0);
+        let s2 = s1.slice(0);
+        assert_eq!(&0, s2.get(0));
+        assert_eq!(&1, s2.get(1));
+        let s2 = s1.slice(1);
+        assert_eq!(&2, s2.get(0));
+        assert_eq!(&3, s2.get(1));
+        let s1 = a.slice(1);
+        let s2 = s1.slice(0);
+        assert_eq!(&4, s2.get(0));
+        assert_eq!(&5, s2.get(1));
+        let s2 = s1.slice(1);
+        assert_eq!(&6, s2.get(0));
+        assert_eq!(&7, s2.get(1));
+    }
+}