Earlier quoted context omitted.
I'd say this depends of the complexity of the I/O system. This was the original claim, which you supported: 'Parsing Lisp in Lisp is so easy because it’s free.' The example you were pointing to is explicitly calling a parsing engine of Racket via 'read-syntax'. Actually more complicated than the usual s-expression reader - which does only read s-expressions, but has no further idea about Scheme syntax. Check the usua…
Ah I love computer programmers
I know right?^^