Well I think this code is harder to maintain in the long term than a proper parser. For example you may want foo"bar"baz to parse as two symbols and a string, o

Well I think this code is harder to maintain in the long term than a proper parser. For example you may want foo"bar"baz to parse as two symbols and a string, or (a.b) as a cons. It also looks scary to me because I need to think a bit to be convinced that it works. But looking at code for a parser is surely hard too, and I don’t think any of those are strong enough arguments not to use the code above.