This site is a static rendering of the Trac instance that was used by R7RS-WG1 for its work on R7RS-small (PDF), which was ratified in 2013. For more information, see Home. For a version of this page that may be more recent, see HygienicInclusion in WG2's repo for R7RS-large.

Hygienic­Inclusion

cowan
2014-01-01 00:30:27
3history
source

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, Foment, Owl Lisp

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

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