Something about sizeof(char)

Paolo Carlini pcarlini@suse.de
Mon Jun 21 13:41:00 GMT 2004


Dhruv Matani wrote:

>I'm not too good at figuring out whether code is portable or not, so I'm
>not rally sure that this would be acceptable, so I'd like to hear from
>the experts.
>  
>
>>ffirst_of(string const& src, string const& f)
>>{
>>#if __CHAR_BIT__ <= 8
>>  char table[1 << __CHAR_BIT__] = { 0 };
>>  string::size_type sz = f.size();
>>  string::size_type i;
>>
>>  for (i = 0; i < sz; ++i)
>>    table[(unsigned int)f[i]] = 1;
>>    
>>
A general problem I can easily see with this kind of idea is that its 
profitability
depends way too much on the size of f: what happens when f is big and src is
small? We should work on this issue, first.

Paolo.



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