I'd like to change all the character in a array to lower case.
I find transform() is convenient.

Because the array is large, I don't want to define another array. I
tried:

transform(buffer, buffer + size, buffer, tolower);

From the output, I find it works.
But when I compile it with Visual C++,
I find a warning that says 'Function call with parameters that may be
unsafe'.

I shouldn't use transform that way?
I must define another array to store the result or
do it without transform?

Lambda writes:

> I'd like to change all the character in a array to lower case.
> I find transform() is convenient.
>
> Because the array is large, I don't want to define another array. I
> tried:
>
> transform(buffer, buffer + size, buffer, tolower);
>
> From the output, I find it works.
> But when I compile it with Visual C++,
> I find a warning that says 'Function call with parameters that may be
> unsafe'.
>
> I shouldn't use transform that way?

I see nothing wrong with this. The only thing that's wrong here is your
choice of using Microsoft's technology for learning C++. It's a known cause
of brain rot.

> I must define another array to store the result or
> do it without transform?

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Lambda a écrit :
> I'd like to change all the character in a array to lower case.
> I find transform() is convenient.
>
> Because the array is large, I don't want to define another array. I
> tried:
>
> transform(buffer, buffer + size, buffer, tolower);
>
> From the output, I find it works.
> But when I compile it with Visual C++,
> I find a warning that says 'Function call with parameters that may be
> unsafe'.
>
> I shouldn't use transform that way?

This is a MS feature called check iterator. The compiler warns you that
you may write out of bounds. Are you sure the size is correct ?

> I must define another array to store the result or
> do it without transform?

If you are sure you are right you can silence the compiler by defining:
#define _SECURE_SCL 0

Or using a Windows specific extension:
transform(buffer,buffer+size,
stdext::checked_array_iterator<char*>(buffer, size),
tolower);



--
Michael

On Jul 16, 12:43 pm, Lambda <stephenh...@gmail.com> wrote:
> I'd like to change all the character in a array to lower case.
> I find transform() is convenient.

> Because the array is large, I don't want to define another array. I
> tried:

> transform(buffer, buffer + size, buffer, tolower);

> From the output, I find it works.

Depending on the includes, it's likely to not even compile. And
if it does, the results have undefined behavior.

> But when I compile it with Visual C++,
> I find a warning that says 'Function call with parameters that
> may be unsafe'.

Which one?

> I shouldn't use transform that way?

No.

> I must define another array to store the result or
> do it without transform?

No, but you do have to provide a functional object that is
unambiguous and that works correctly on the data type. You also
should be using std::vector instead of whatever; it would make
life a lot easier.

And finally, of course, you should be aware that upper to lower
case is not necessarily a one to one mapping, and that it is
very locale dependent.

--
James Kanze (GABI Software) email:james.kanze@gmail.com
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