Re: Wierd Warning

[Frank D. Engel, Jr.]

> Now, look at the signature of the cString method in NSString.h:
>           - (const char*) cString;
> the 'const' here means that the returned string MUST NOT be modified.

Exactly, therefor the (char *) cast... since I do modify it later on.

>> Therefore, you should declare pat as:
>>       const char* pat=[pattern cString];
>> and you should declare: 
>>       BOOL initPattern(const char** pattern,BOOL flag)
>> In  initPattern, you  cannot modify  the content  of the  memory 
>>block
>> pointed  by  (*pattern)  (that  is,  (*pattern)[i]).   You  can  
>>still
>> allocate a new memory block and return it thru (*pattern).
>
>Unfortunately, that's not really an option, as pattern will be passed 
>to
>several other functions from initPattern, which all will modify it.


Uh... you seem to miss the point here.  The whole explanation for
returning a CONSTant pointer is that the caller should NEVER change the
data it points to.  Casting to a non-CONST pointer allows assignment to
the mutable-type pointer, but it still results in potentially changing
the data that the CONSTant pointer pointed to, which you should not be
doing.  Instead, you should make a COPY of that data, and work with the
COPY.

The warning you recieved should have pointed to the earlier line, where
you made the cast; that is much more likely to be a problem.


=====
=======
Frank D. Engel, Jr.

Modify the equilibrium of the vertically-oriented particle decelerator to 
result in the reestablishment of its resistance to counterproductive 
atmospheric penetration.

__________________________________________________
Do you Yahoo!?
Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
http://platinum.yahoo.com