I probably found the answer myself, it's overgeneration, right?! You lose control over substructures, like the ":" pairs in dicts, or the initializer part in C-style for-loops, if you allow to recurse in generic expression parsing.
I probably found the answer myself, it's overgeneration, right?! You lose control over substructures, like the ":" pairs in dicts, or the initializer part in C-style for-loops, if you allow to recurse in generic expression parsing.