[Chicken-users] Macro returning multiple nodes?

[Mathieu]

Hi everyone,

Writing macros with the er-macro-transformer syntax has been a charm so far.

But I am now trying to accomplish something that might not make sense.

I would like to use the following syntax in my code:

            ;; make the get-session-response

            (make-get-session-response

              (get-record-values

                (session-row

                  session-id

                  name

                  start-date

                  weeks-count)))

And have it expended to:

            ;; make the get-session-response

            (make-get-session-response

              (session-row-session-id session-row)

              (session-row-name session-row)

              (session-row-start-date session-row)

              (session-row-weeks-count session-row))

That would somehow imply having a macro node replaced by multiple sequential nodes in the AST.

My best guess so far would be:

            (define-syntax get-record-values

              (er-macro-transformer

                (lambda (exp rename compare)

                  ;; parse the _expression_

                  (let* ((record-_expression_ (cadr exp))

                         (record-symbol (list-ref record-_expression_ 0))

                         (record-values (cdr record-_expression_)))

                  

                    ;; produce the statements to get the record values

                    `,@(map

                      (lambda (record-value)

                        `(,(symbol-append record-symbol '- record-value) ,record-symbol))

                      record-values)))))

But that does not work, probably for the suspected reason mentioned above.

Is that something that I could achieve?

Thanks in advance,

Mathieu