Further slight simplifications

1 files changed, 6 insertions, 6 deletions

diff --git a/numpy/core/shape_base.py b/numpy/core/shape_base.py
index c65849752..732ea30ae 100644
--- a/numpy/core/shape_base.py
+++ b/numpy/core/shape_base.py
@@ -399,8 +399,8 @@ def _block_check_depths_match(arrays, parent_index=[]):
             )
         )
     elif type(arrays) is list and len(arrays) > 0:
-        indexes, arr_ndims = zip(*[_block_check_depths_match(arr, parent_index + [i])
-                                 for i, arr in enumerate(arrays)])
+        indexes, arr_ndims = zip(*(_block_check_depths_match(arr, parent_index + [i])
+                                   for i, arr in enumerate(arrays)))
 
         first_index = indexes[0]
         for i, index in enumerate(indexes):
@@ -422,14 +422,14 @@ def _block_check_depths_match(arrays, parent_index=[]):
         return parent_index, _nx.ndim(arrays)
 
 
-def _block(arrays, max_depth, max_ndim):
+def _block(arrays, max_depth, result_ndim):
     def atleast_nd(a, ndim):
         # Ensures `a` has at least `ndim` dimensions by prepending
         # ones to `a.shape` as necessary
         return array(a, ndmin=ndim, copy=False, subok=True)
 
     def block_recursion(arrays, depth=0):
-        if type(arrays) is list:
+        if depth < max_depth:
             if len(arrays) == 0:
                 raise ValueError('Lists cannot be empty')
             arrs = [block_recursion(arr, depth+1) for arr in arrays]
@@ -437,7 +437,7 @@ def _block(arrays, max_depth, max_ndim):
         else:
             # We've 'bottomed out' - arrays is either a scalar or an array
             # depth == max_depth
-            return atleast_nd(arrays, max(max_depth, max_ndim))
+            return atleast_nd(arrays, result_ndim)
 
     return block_recursion(arrays)
 
@@ -592,4 +592,4 @@ def block(arrays):
     """
     bottom_index, arr_ndim = _block_check_depths_match(arrays)
     list_ndim = len(bottom_index)
-    return _block(arrays, list_ndim, arr_ndim)
+    return _block(arrays, list_ndim, max(arr_ndim, list_ndim))