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Case­Insensitivity

cowan
2012-08-22 08:30:43
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Symbols

Racket, Gauche, Gambit, Chicken, Bigloo, scsh, Guile, Kawa, Chibi, Chez, Vicare, Larceny, Ypsilon, Mosh, IronScheme, NexJ, KSi, SigScheme, Shoe, RScheme, Scheme 7, BDC, Rep, Schemik, Llava, Sizzle, Spark, Femtolisp, Dfsch, Owl Lisp return #f to (eq? 't 'T).

MIT, Scheme48, SISC, SCM, STklos, TinyScheme, Scheme 9, Dream, XLisp, Elk, UMB, VX, Oaklisp, SXM, Inlab return #t.

Preferred case is upper case

I also decided to check the case-insensitive implementations using (string=? (symbol->string 't) "T") to see which ones converted symbols to upper case internally. Only XLisp (which is not really Scheme-compliant) and Oaklisp (which is somewhat R3RS-compliant) did so.

Character names

Is #\Space a valid constant?

Racket, Gauche, MIT, Bigloo, Scheme48, Guile, Kawa, Chibi, Chez, NexJ, STklos, KSi, SigScheme, TinyScheme, Scheme 9, Dream, RScheme, Rep, Elk, Oaklisp, Llava, SXM, Spark, Dfsch, Inlab accept #\Space.

Gambit, Chicken, scsh, Vicare, Ypsilon, Mosh, IronScheme, Shoe, Scheme 7, Schemik, UMB, Sizzle, FemtoLisp, Owl Lisp reject #\Space.

Boolean constants

Gambit, TinyScheme, Scheme 7, VX, Sizzle, Owl Lisp do not accept #T as equivalent to #t.

The other Schemes in the test suite do.

Inexact constants

All Schemes in the test suite accept E as well as e in inexact constants (except those without inexact number support).