e.g. "this is how machine-generated parsers know to skip blanks and comments" The run time implementation could be better; we don't really want to just discard trivia because it's useful for e.g. doc comments and the like. BUT for now this is fine.
More robust testing. Error messages would be nice but.
But regular expressions are underpowered and verbose
It will help with testing and profiling It breaks pyright (it's probably time to abandon pyright)
