How to create a macro that generates another macro in SISC / Scheme? -


in guile or using srfi-46 possible shown in specifying custom ellipsis identifier. possible in sisc or "pure scheme" r5rs?

i know possible without using ellipsis, if need use inner ellipsis example bellow?

(define-syntax define-quotation-macros   (syntax-rules ()     ((_ (macro-name head-symbol) ...)      (begin (define-syntax macro-name               (syntax-rules ::: ()                 ((_ x :::)                  (quote (head-symbol x :::)))))             ...)))) (define-quotation-macros (quote-a a) (quote-b b) (quote-c c)) (quote-a 1 2 3) ⇒ (a 1 2 3)

the macro expander used in sisc, psyntax, supports different way inner ellipses, using ... macro. can write applying ... macro each inner ellipses want use:

(define-syntax define-quotation-macros   (syntax-rules ()     ((_ (macro-name head-symbol) ...)      (begin (define-syntax macro-name               (syntax-rules ()                 ((_ x (... ...))                  '(head-symbol x (... ...)))))             ...))))

or can apply outer form ellipses within supposed inner:

(define-syntax define-quotation-macros   (syntax-rules ()     ((_ (macro-name head-symbol) ...)      (begin (define-syntax macro-name               (... (syntax-rules ()                      ((_ x ...)                       '(head-symbol x ...)))))             ...))))

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