Re: A Certain Size/sizeof

From: Ulrich Eckhardt (doomster_at_knuut.de)
Date: 11/14/03 

Date: Fri, 14 Nov 2003 21:54:34 +0100

Gene Wirchenko wrote:
> int BufferTestNumbers[][17]=
> { ... };
>
> std::string
> TestBuffer[sizeof(BufferTestNumbers)/sizeof(int)/17];
>
> Truly an ugly array size expression, no?

Firstly, sizeof is not a function, therefore 'sizeof BufferTestNumbers'
doesn't need brackets. 'sizeof (int)' is an example the second version to
invoke that operator and that takes a typename in brackets, but still not
a function.

> Is there a way to declare TestBuffer without the magic number? I
> would prefer to keep the declaration of BufferTestNumbers as it is (or
> with very minor changes) as it is easy to adjust should I want other
> test cases. I ask for both C and C++.

assuming I had
  int array[] = { 1,2,3,4,5,8,12 };
I usually do
  size_t const count = sizeof array / sizeof *array;

Adapting that to a more-dimensional array is left as exercise for
the reader.

Uli 

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