That at least isn't true in terms of the Chomsky grammar hierarchy. You can have both angle brackets operators and delimiters in a CFG (context-free grammar). I

That at least isn't true in terms of the Chomsky grammar hierarchy. You can have both angle brackets operators and delimiters in a CFG (context-free grammar). It might be a limitation of their parsing tech (e.g. LL(1) would have that issue, probably LR too). No problem for general CFG parsers though (if you can write a BNF grammar for it, that's the CFG grammar for it).