BUG: #9798 index_col shouldn't accept the value True

check at ``TextFileReader`` ``clean_options``

Author: lucas

pandas/io/parsers.py

@@ -652,6 +652,8 @@ def _clean_options(self, options, engine):
         # really delete this one
         keep_default_na = result.pop('keep_default_na')
 
+        if index_col is True:
+            raise ValueError("The value of index_col couldn't be 'True'")
         if _is_index_col(index_col):
             if not isinstance(index_col, (list, tuple, np.ndarray)):
                 index_col = [index_col]
@@ -905,7 +907,7 @@ def _make_index(self, data, alldata, columns, indexnamerow=False):
 
     def _get_simple_index(self, data, columns):
         def ix(col):
-            if not (isinstance(col, compat.string_types) or col is True):
+            if not isinstance(col, compat.string_types):
                 return col
             raise ValueError('Index %s invalid' % col)
         index = None