Moved num_workers ValueError

Erotemic · Erotemic · commit cb44b8164478 · 2017-12-05T11:18:17.000-05:00
diff --git a/torch/utils/data/dataloader.py b/torch/utils/data/dataloader.py
@@ -219,9 +219,6 @@ def __init__(self, loader):
             # prime the prefetch loop
             for _ in range(2 * self.num_workers):
                 self._put_indices()
-        elif self.num_workers < 0:
-            raise ValueError('num_workers cannot be negative; '
-                             'use num_workers=0 to disable multiprocessing.')
 
     def __len__(self):
         return len(self.batch_sampler)
@@ -364,6 +361,10 @@ def __init__(self, dataset, batch_size=1, shuffle=False, sampler=None, batch_sam
         if sampler is not None and shuffle:
             raise ValueError('sampler is mutually exclusive with shuffle')
 
+        if self.num_workers < 0:
+            raise ValueError('num_workers cannot be negative; '
+                             'use num_workers=0 to disable multiprocessing.')
+
         if batch_sampler is None:
             if sampler is None:
                 if shuffle:
