Harald van Dijk <truedfx@[EMAIL PROTECTED]
> writes:
> On Sun, 11 May 2008 20:01:34 +0200, Eligiusz Narutowicz wrote:
>> Harald van Dijk <truedfx@[EMAIL PROTECTED]
> writes:
>>> On Sun, 11 May 2008 09:10:07 -0700, Tomás Ó hÉilidhe wrote:
>>>> On May 11, 2:29 pm, Chris H <ch...@[EMAIL PROTECTED]
> wrote:
>>>>> >If anything I would imagine
>>>>> >it makes the implementation more complex if one tries to enforce a
>>>>> >specific order between char and unsigned.
>>>>>
>>>>> I would have thought if tokens are always in a set order it is
easier
>>>>> to parse.
>>>>
>>>>
>>>> Imagine you're writing a program that has commandline options, e.g.:
>>>>
>>>> prog.exe -t -e -f
>>>>
>>>> Now imagine the code you'd have in main for it. You might have some
>>>> sort of switch statement to check whether the command line option is
>>>> 't' or 'e'. If you were to impose a strict order on the commadline
>>>> options, then you'd have to keep some sort of list of what previous
>>>> command line options appeared and in what order. Sounds like a
useless
>>>> and inefficient restriction to me.
>>>
>>> This is simpler than allowing options to appear in any order.
>>>
>>> if (streq(*argv, "-t")) {
>>> opt_t = true;
>>> argv++;
>>> }
>>>
>>> if (streq(*argv, "-e")) {
>>> opt_e = true;
>>> argv++;
>>> }
>>>
>>> if (streq(*argv, "-f")) {
>>> opt_f = true;
>>> argv++;
>>> }
>>
>> I do not see how that is any simpler that a for loop with switch where
>> there is only one argv++.
>
> True, you could easily convert it to
>
> for (;;) {
> if (streq(*argv, "-t")) {
> opt_t = true;
> argv++;
> } else if (streq(*argv, "-e")) {
> opt_e = true;
> argv++;
> } else if (streq(*argv, "-f")) {
> opt_f = true;
> argv++;
> } else
> break;
> }
No. You would take out the argv++ into the for loop.
>
> and change that to use switch or whatever method you want, but if you do
> this, you no longer guard against -t -t, which was an error when the
order
> was forced, but would be silently accepted here. To fix that (assuming
you
> don't want to allow it -- with the original case of unsigned char, you
> wouldn't) you need to add extra checks. This isn't difficult, but
slightly
> less simple than having a fixed order.
No it isn't. I do not understand what you mean by -t -t being a problem
and how using if statements one after the other solves this. Last
occurrence rules.
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