wiki:HygienicInclusion

Version 1 (modified by cowan, 4 years ago) (diff)

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Are inclusions hygienic?

Given the macro

(define-syntax m
  (syntax-rules ()
    ((_) (lambda (a) (include "add.scm")))))

where add.scm contains (+ a 1), is the a that is bound inside the macro the same as the a in add.scm? In particular, does ((m) 32) evaluate to 33, or is a reported as an undefined variable?

Evaluates to 33: Racket, Gambit, Guile, Kawa, SISC, Chez, Mosh, IronScheme, SXM

a is undefined: Gauche, Chicken, Chibi, STklos, S7, Owl Lisp

include is undefined: MIT, Bigloo, Scheme48/scsh, SCM, Vicare, Larceny, Ypsilon, Scheme 9

No syntax-rules macros: NexJ, JScheme, SigScheme, Shoe, TinyScheme, Dream, BDC, XLisp, Schemik, Elk, UMB, Oaklisp, Llava, Sizzle, FemtoLisp, Dfsch, Inlab

Uninterpretable error output: KSi, RScheme