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Source for wiki CaseInsensitivity version 5

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cowan

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98.14.173.81

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CaseInsensitivity

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=== The Cowan-Gleckler Show ===

John says: Case insensitivity by default is getting to be rare these days.  Of my 40
implementations, only MIT, Scheme48 (but not scsh), SISC, SCM, STklos,
!TinyScheme, Scheme 9, Dream, XLISP, Elk, UMB, VX, Oaklisp reply `#t` to
`(eq? 't 'T)`.

Arthur says: 13/40 is not rare.  It's almost a third.

John says:  Okay, but between you and me and the bedpost, the only ones that count for much nowadays are the first four, five, or six, depending.

Arthur says: But how many of the case-sensitive implementations count for much?  If we're to compute a ratio, we need a comparable numerator and denominator.

John says:

Okay, okay.  I reran the test with my current suite of 45 Schemes, with the following results:

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 `#f`.

So you tell me how big the denominator should be; I make it at least ten.  But you're right, it's not rare.

=== 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.

time

2012-05-21 22:09:32