syntax-rules: (define-syntax foo (syntax-rules () ((foo (a ...) (b ...)) '((a b) ...))))

これは意外。。

• scheme-faq-macros

	;; http://community.schemewiki.org/?scheme-faq-macros
	(define-syntax foo
	(syntax-rules ()
	((foo (a ...) (b ...)) '((a b) ...))))
	(foo (1 2) (3 4 5))
	; -> ((1 3) (2 4))
	(foo (1 2 3 4 5) (6 7 8 9 10))
	; -> ((1 6) (2 7) (3 8) (4 9) (5 10))
	(define-syntax foo
	(syntax-rules ()
	((_ (a ...)(b ...) ...)
	'(((a b) ...) ...))))
	(foo (1 2)(3 4)(5 6 7))
	; -> (((1 3) (1 4)) ((2 5) (2 6) (2 7)))

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