Re: Why is "Hello World" const char* ?

From: CBFalconer (cbfalconer_at_yahoo.com)
Date: 02/06/05 

Date: Sun, 06 Feb 2005 20:46:39 GMT

Ron Natalie wrote:
> Luke Wu wrote:
>
>> In C, a string literal (like "Hello") in value context (like the
>> right side of an assignment= operator) evaluates to a pointer
>> value of type (const char*) that points to the first character.
>
> Nope, it evaluates to an array of char, which converts to pointer
> to char. The characters are effectively const (it is undefined
> behvaior to attempt to change them), but the type of the
> expression is not const char*. (except when sizeof or & is
> applied to the array value).
>
> It's effectively the same in C++, except C++ defines a formal
> array-to-pointer conversion.

However it is advisable to declare such strings as:

  const char *foo = "foobar";

so that the C compiler can emit suitable warnings on misuse, such
as trying to alter it with such things as *foo = 'F'; Note that
foo = "barfoo"; is perfectly legal, except you may never find the
"foobar" string again. 

-- 
"If you want to post a followup via groups.google.com, don't use
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