Merge pull request #120 from scart97/add_comments_signature

Comment explaining signature fix on L

Author: jph00

nbs/01_foundation.ipynb

@@ -1728,6 +1728,18 @@
    ],
    "source": [
     "#hide\n",
+    "\n",
+    "# Here we are fixing the signature of L. What happens is that\n",
+    "# the __call__ method on the MetaClass of L shadows the __init__\n",
+    "# giving the wrong signature [1].\n",
+    "\n",
+    "# The solution adopted tries to not import the inspect module \n",
+    "# inside the lib code (notice that this cell is not exported)\n",
+    "# because it's really slow, but instead relies on pickling the\n",
+    "# correct signature and loading it.\n",
+    "\n",
+    "# [1] https://stackoverflow.com/questions/49740290/call-from-metaclass-shadows-signature-of-init\n",
+    "\n",
     "def _f(items=None, *rest, use_list=False, match=None): ...\n",
     "pickle.dumps(inspect.signature(_f))"
    ]