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Re: Variable naming issue

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On 08/05/2017 19:47, David Kleinecke wrote:
> On Monday, May 8, 2017 at 2:53:34 AM UTC-7, Bart wrote:
>> On 08/05/2017 10:35, bartc wrote:
>>
>>> (not C code):
>>>
>>>     when 'A'..'Z','a'..'z','$','_' then
>>>     when 'A'..'Z','a'..'z','$','_','0'..'9' then
>>>
>>> So providing support for "$" doesn't require any more lines, it just
>>> needs a minor tweak on two lines. (And no, it won't work on EBCDIC, but
>>> I don't care!)
>>
>> Actually, if this was translated to C, as would be necessary to run on
>> such a machine, then it might well do. Because C case values are all
>> separate. Even more reason not to care.
>
> Standard way to handle
>     when 'A'..'Z','a'..'z','$','_' then
> is to map the characters through a character array to two
> characters and do an "if" on the result
>     if (map[x] == 'a') ....
>
> Obviously generalizable to more cases.
>

Not sure what you mean here.

But that second sequence is actually used to initialise a character map 
(char[256]), where each element is 1 if the corresponding character 
belongs in the set, 0 otherwise).

Testing such a map was a fast way, after a particular kind of token was 
identified, to probe for the end of the token:

   while (alphamap[*lxsptr++]);

If you mean using a map to classify sets of characters as alpha etc, 
then that's a technique I used in the 80s; I like a change...

-- 
bartc

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Variable naming issue maximus fl <ajones2600@gmail.com> - 2017-04-24 16:17 -0700
  Re: Variable naming issue David Kleinecke <dkleinecke@gmail.com> - 2017-04-24 16:28 -0700
  Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 01:09 +0100
    Re: Variable naming issue Noob <root@127.0.0.1> - 2017-04-25 09:37 +0200
      Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 10:40 +0100
        Re: Variable naming issue David Brown <david.brown@hesbynett.no> - 2017-04-25 13:07 +0200
          Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 13:24 +0100
            Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 13:27 +0100
            Re: Variable naming issue Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-25 13:59 +0100
              Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 14:20 +0100
                Re: Variable naming issue Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-25 14:27 +0100
                Re: Variable naming issue Keith Thompson <kst-u@mib.org> - 2017-04-25 11:52 -0700
                Re: Variable naming issue Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-04-25 13:40 -0700
                Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 22:14 +0100
                Re: Variable naming issue David Brown <david.brown@hesbynett.no> - 2017-04-26 00:16 +0200
                Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-26 00:13 +0100
                Re: Variable naming issue David Brown <david.brown@hesbynett.no> - 2017-04-26 10:10 +0200
                Re: Variable naming issue supercat@casperkitty.com - 2017-04-25 14:33 -0700
                Re: Variable naming issue Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-04-25 06:39 -0700
                Re: Variable naming issue Robert Wessel <robertwessel2@yahoo.com> - 2017-04-25 09:35 -0500
              Re: Variable naming issue Gareth Owen <gwowen@gmail.com> - 2017-04-25 18:39 +0100
                Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 18:49 +0100
                Re: Variable naming issue David Kleinecke <dkleinecke@gmail.com> - 2017-04-25 11:19 -0700
                Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-25 19:31 +0100
                Re: Variable naming issue Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-25 23:36 +0100
                Re: Variable naming issue David Kleinecke <dkleinecke@gmail.com> - 2017-04-25 17:04 -0700
                Re: Variable naming issue Robert Wessel <robertwessel2@yahoo.com> - 2017-04-26 00:32 -0500
            Re: Variable naming issue David Brown <david.brown@hesbynett.no> - 2017-04-25 16:02 +0200
            Re: Variable naming issue Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-02 05:25 -0700
              Re: Variable naming issue supercat@casperkitty.com - 2017-05-02 10:04 -0700
                Re: Variable naming issue Tim Rentsch <txr@alumni.caltech.edu> - 2017-05-05 03:06 -0700
          Re: Variable naming issue supercat@casperkitty.com - 2017-04-25 07:12 -0700
          Re: Variable naming issue Robert Wessel <robertwessel2@yahoo.com> - 2017-04-25 09:48 -0500
            Re: Variable naming issue Robert Wessel <robertwessel2@yahoo.com> - 2017-04-25 09:52 -0500
        Re: Variable naming issue Noob <root@127.0.0.1> - 2017-04-26 08:46 +0200
          Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-26 11:46 +0100
          Re: Variable naming issue bartc <bc@freeuk.com> - 2017-04-26 12:00 +0100
        Re: Variable naming issue gordonb.o1c18@burditt.org (Gordon Burditt) - 2017-05-07 22:25 -0500
          Re: Variable naming issue bartc <bc@freeuk.com> - 2017-05-08 10:35 +0100
            Re: Variable naming issue bartc <bc@freeuk.com> - 2017-05-08 10:53 +0100
              Re: Variable naming issue David Kleinecke <dkleinecke@gmail.com> - 2017-05-08 11:47 -0700
                Re: Variable naming issue bartc <bc@freeuk.com> - 2017-05-08 19:59 +0100
      Re: Variable naming issue gazelle@shell.xmission.com (Kenny McCormack) - 2017-04-25 10:43 +0000
    Re: Variable naming issue Robert Wessel <robertwessel2@yahoo.com> - 2017-04-25 09:33 -0500
  Re: Variable naming issue Keith Thompson <kst-u@mib.org> - 2017-04-24 17:26 -0700
    Re: Variable naming issue maximus fl <ajones2600@gmail.com> - 2017-04-24 18:18 -0700
  Re: Variable naming issue scott@slp53.sl.home (Scott Lurndal) - 2017-04-25 14:48 +0000

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