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Scheme sucks

Name: Anonymous 2011-01-28 10:46

because HAS NO MACROS.

Name: " 2011-01-28 11:54

Macro in LISP.



(defmacro aif (cond then else)

  `(let ((it ,cond))

     (if it ,then ,else)))

Macro in Scheme/Racket.



#lang racket

(require racket/stxparam)

 

(define-syntax-parameter it (λ (stx) (raise-syntax-error 'anaphora "missed context" stx)))

 

(define-syntax-rule (aif cond then else)

  (let ([temp cond])

    (syntax-parameterize ([it (make-rename-transformer #`temp)])

                         (if temp then else))))

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