- DHParser/ebnf.py: TODO regarding atomic grouping within res added

DHParser/ebnf.py

@@ -703,9 +703,10 @@ class EBNFCompiler(Compiler):
     def _check_rx(self, node: Node, rx: str) -> str:
         """
         Checks whether the string `rx` represents a valid regular
-        expression. Makes sure that multiline regular expressions are
-        prepended by the multiline-flag. Returns the regular expression string.
+        expression. Makes sure that multi-line regular expressions are
+        prepended by the multi-line-flag. Returns the regular expression string.
         """
+        # TODO: Support atomic grouping: https://stackoverflow.com/questions/13577372/do-python-regular-expressions-have-an-equivalent-to-rubys-atomic-grouping
         flags = self.re_flags | {'x'} if rx.find('\n') >= 0 else self.re_flags
         if flags:
             rx = "(?%s)%s" % ("".join(flags), rx)