mypy will compile the shapetracker, no speed up

tinygrad/shape/__init__.py

@@ -39,7 +39,7 @@ class View:
     return Variable.sum(ret)
 
   @property
-  def expr(self):
+  def expr(self) -> str:
     return 'idx=' + str(self.expr_node(Variable('idx', 0, prod([x[0] for x in self.shape_strides])-1)))
 
   # generate an expression if you have a variable or expression for each index
@@ -47,20 +47,13 @@ class View:
     return Variable.sum([Variable.num(self.offset+offset)] + [Variable(idxs[i], 0, sh-1)*st for i,(sh,st) in enumerate(zip(self.shape, self.strides)) if sh != 1 and st != 0])
 
 class ZeroView:
-  __slots__ = ('old_shape', 'arg', 'shape')
+  __slots__ = ('old_shape', 'arg', 'shape', 'contiguous', 'strides', 'offset')
 
   def __init__(self, old_shape:Tuple[int, ...], arg):
     self.old_shape, self.arg = old_shape, arg
     self.shape : Tuple[int, ...] = tuple([y-x for x,y in self.arg])
-
-  @property
-  def strides(self): raise NotImplementedError("ZeroView doesn't have strides")
-
-  @property
-  def offset(self): raise NotImplementedError("ZeroView doesn't have offset")
-
-  @property
-  def contiguous(self): return False
+    # fake properties
+    self.strides, self.contiguous, self.offset = strides_for_shape(self.shape), False, 0
 
   def expr_idxs(self, idxs, offset=0): raise NotImplementedError("ZeroView doesn't have expr_idxs")
 
@@ -73,7 +66,7 @@ class ZeroView:
     return Variable.ands(expr)
 
   @property
-  def expr(self):
+  def expr(self) -> str:
     max_idx = prod([y-x for x,y in self.arg])
     return 'valid=' + str(self.expr_node(Variable('valid', 0, 1), Variable('idx', 0, max_idx-1)))
 
@@ -131,7 +124,7 @@ class ShapeTracker:
       else: idx = v.expr_node(idx)
     return idx, valid
   
-  def expr(self):
+  def expr(self) -> str:
     idx, valid = self.expr_node()
     if valid is not None and str(valid) != "valid": return f"valid={valid};idx={idx}"
     else: return f"idx={idx}"