Add the op.

src/device.rs

@@ -1,4 +1,4 @@
-use crate::{DType, Storage};
+use crate::{storage::Storage, DType};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum Device {

src/lib.rs

@@ -1,9 +1,9 @@
 mod device;
 mod dtype;
+mod op;
 mod storage;
 mod tensor;
 
 pub use device::Device;
 pub use dtype::DType;
-use storage::Storage;
 pub use tensor::Tensor;

src/op.rs

@@ -0,0 +1,7 @@
+use crate::Tensor;
+
+#[allow(dead_code)]
+pub(crate) enum Op {
+    Add(Tensor, Tensor),
+    Mul(Tensor, Tensor),
+}

src/storage.rs

@@ -1,3 +1,5 @@
+use crate::{DType, Device};
+
 #[allow(dead_code)]
 pub(crate) enum Storage {
     Cpu {
@@ -5,3 +7,17 @@ pub(crate) enum Storage {
         buffer: Vec<u8>,
     },
 }
+
+impl Storage {
+    pub(crate) fn device(&self) -> Device {
+        match self {
+            Self::Cpu { .. } => Device::Cpu,
+        }
+    }
+
+    pub(crate) fn dtype(&self) -> DType {
+        match self {
+            Self::Cpu { dtype, .. } => *dtype,
+        }
+    }
+}

src/tensor.rs

@@ -1,40 +1,49 @@
-use crate::{DType, Device, Storage};
+use crate::{op::Op, storage::Storage, DType, Device};
+use std::sync::Arc;
 
-pub struct Tensor {
+#[allow(dead_code)]
+pub(crate) struct Tensor_ {
     storage: Storage,
     shape: Vec<usize>,
     stride: Vec<usize>,
+    op: Option<Op>,
 }
 
+pub struct Tensor(Arc<Tensor_>);
+
 impl Tensor {
     pub fn zeros(shape: &[usize], dtype: DType, device: Device) -> Self {
         let storage = device.zeros(shape, dtype);
-        Self {
+        let tensor_ = Tensor_ {
             storage,
             shape: shape.to_vec(),
             stride: vec![1; shape.len()],
-        }
+            op: None,
+        };
+        Tensor(Arc::new(tensor_))
+    }
+
+    pub fn dtype(&self) -> DType {
+        self.0.storage.dtype()
     }
 
     pub fn device(&self) -> Device {
-        match self.storage {
+        self.0.storage.device()
-            Storage::Cpu { .. } => Device::Cpu,
-        }
     }
 
     pub fn shape(&self) -> &[usize] {
-        &self.shape
+        &self.0.shape
     }
 
     pub fn stride(&self) -> &[usize] {
-        &self.stride
+        &self.0.stride
     }
 
     pub fn rank(&self) -> usize {
-        self.shape.len()
+        self.0.shape.len()
     }
 
     pub fn elem_count(&self) -> usize {
-        self.shape.iter().product()
+        self.0.shape.iter().product()
     }
 }