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 ImproperLists in WG2's repo for R7RS-large.


2014-12-28 09:59:33

I tested memq on an improper list, first against an object that appears in the list, then against an object that does not.

In the first case, all 39 Schemes return the tail of the improper list except Mosh, which signals an error.

In the second case, the following Schemes signal an error: Racket, MIT, Gambit, Scheme48/scsh, Guile, SISC, Chez, SCM, Ikarus/Vicare, Larceny, Ypsilon, IronScheme, NexJ, KSi, SigScheme, Shoe, Dream, BDC, Rep, Schemik, Elk, UMB, VX, Oaklisp, Owl Lisp, Scheme 9.

The following Schemes quietly return #f: Gauche, Chicken, Bigloo, Guile, Chibi, STklos, S7, XLisp, Sagittarius.