Add the op.

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 {
-            Storage::Cpu { .. } => Device::Cpu,
-        }
+        self.0.storage.device()
     }
 
     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()
     }
 }