If you want to handle the error and also bubble it up, maybe even changing the what error bubbles up, you can just return an error from within the catch block a

If you want to handle the error and also bubble it up, maybe even changing the what error bubbles up, you can just return an error from within the catch block after doing whatever handling you want. Either the captured error or something else. Specifically for recursive descent parsers, I pass around a reference to an regular struct that acts as an ErrorInfo object, and use that to pass diagnostic information up the stack. Control flow is still managed by the error returns, any additional info goes in the parameter. There is (was?) a proposal to add that capability to the language but Im not sure it had much traction.