[Jprogramming] Mistake in the NuVoc page for sequential machine

[Henry Rich]

Maybe they're not logically disjoint, but an input symbol must choose a 
row of the state machine, and you need different rows for 0 and 1.  
Character 0 must not map to the 'hexdigits' input class.

Henry Rich

On 9/16/2019 10:41 AM, Ian Clark wrote:
>> The red zero should be omitted.
> I want to dispute this. Input classes don't need to be disjoint.
>
> I can't recall seeing any document which says they should -- but tell me if
> I'm wrong, because any such document needs to be fixed.
>
> IMO the example is simpler to follow if (quote) "the hexadecimal
> characters" means exactly what is commonly understood, viz. 0 to 9 with 'a'
> to 'f', and with 'A' to 'F' for good measure. Even if '0' is shared with
> another class. (But isn't that logical? '0' is dual-use.)
>
> Maybe the NuVoc page for (;:) could do with making it clearer.
>
> Come to think of it, the NuVoc page for (;:) could do with making a lot of
> things clearer.
> (I'll see to it.)
>
> On Mon, 16 Sep 2019 at 08:16, Arnab Chakraborty <arnabc74 at gmail.com> wrote:
>
>> I just want to report a minor inconsistency in the NuVoc page for
>> sequential machine:
>>
>> In the example for recognizing C hex strings, we have
>>
>> We see that the input characters are in 4 classes
>>
>>     - the character 0
>>     - the character x
>>     - the hexadecimal characters *0*123456789abcdefABCDEF
>>     - all other characters.
>>
>>
>> The red zero should be omitted. The code BTW is correct.
>>
>>
>> Thanks and regards,
>>
>> Arnab
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