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Re: FEATURE-CASEQ and TARGET-FEATURES



    Date: 25 November 1980 18:12-EST
    From: Robert W. Kerns <RWK>
    To:   NIL-I

    (FETURECASEQ 'LOCAL-FEATURES
      ((AND MACLISP (NOT FORMAT)) (PRINT "What a loss"))
      (FRANZ (ERROR))
      ((OR MULTICS LISPM) (PRINT "Big address space"))
      (T "I'm lost!"))

    (FEATURE-SELECT-ALL 'LOCAL-FEATURES
      ....)
    [The same, but perform ALL clauses for which FEATUREP test wins].

    What think you?
-----
Well, calling it xCASEQ is probably a bad idea since the AND/OR
idea is not valid in CASEQ. Probably something like FEATURE-COND
or FEATURE-TEST would be more flavorful if you wanted to allow 
AND/OR/NOT to be in the list. How about FEATURE-TEST for finding
first clause that works and FEATURE-TESTS for finding all clauses
that work...?

In general, I think this concept of TARGET-FEATUREs, etc. is really
the right way to go. I think we have seen in Macsyma and NIL that
the current concept of features is too restrictive and ambiguous 
to be very reliable.