Re: DIGIT-WEIGHT/DIGITP and funny input bases

[Glenn S. Burke <GSB at MIT-ML>]

    Date: 7 October 1980 18:17-EDT
    From: Robert W. Kerns <RWK at MIT-MC>
        Date: 7 October 1980 16:08-EDT
        From: Glenn S. Burke <GSB at MIT-ML>
            Date: 7 October 1980 04:26-EDT
            From: Robert W. Kerns <RWK at MIT-MC>
            Does anybody have any examples where you would?
        Ok, the next version of FORMAT will autoload optimal strings so it
        can "parse" the parameters.
    How is this an example?  Those digits represent numbers, I claim
    you don't care at all about the weights of the individual
    characters, you care about the number that the sequence of digits
    represent!
That is true.  But what kind of interface is provided?  I am at some
point in a string, and the next character(s) may be digits, and if so
i want the value.  Will you provide a routine which will then take
a string, the input radix, and a starting index, and return TWO values
(the number or NIL if none, and the new position in the string)?  And
a mess of other flags to tell it that i don't want shifted, exponential,
or flonum formats recognized?  If i had to find the end of the "string"
of digits, then i have to iterate down the string, and i might as well
just collect the number at the same time.  I'm not saying that
INPUT-FIXNUM is not called for, but that in places where one is not
augmenting or supporting the full glory of Lisp's number syntax
DIGIT-WEIGHT may be called for, and INPUT-FIXNUM (or hairily called
variants) would be cumbersome to use and overkill.