Bad? Pointer question

This is a discussion on Bad? Pointer question within the C++ Programming forums, part of the General Programming Boards category; Code: #include <iostream> void test(char *str); int main ( void ) { char a[] = "asdf"; test(a); return 0; } ...

  1. #1
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    Bad? Pointer question

    Code:
    #include <iostream>
    
    void test(char *str);
    
    int main ( void )
    {
    	char a[] = "asdf";
    
    	test(a);
    
    	return 0;
    }
    
    void test(char *str)
    {
    	while(*str != NULL)
    	{
    		std::cout << *str;
    		str++;
    	}
    }
    Is that bad? I was just playing around, and I thought about trying something like that. It works, from atleast what I can tell.

  2. #2
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    not bad and not good, use 0 probably
    Nana C++ Library is a GUI framework that designed to be C++ style, cross-platform and easy-to-use.

  3. #3
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    The more I think about it, the more it seems okay, but I'm not 100% positive

  4. #4
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    It would be better like this
    Code:
    #include <iostream>
    
    using namespace std;
    
    void test(char *str);
    
    int main ( void )
    {
    	char a[] = "asdf";
    
    	test(a);
    
    	return 0;
    }
    
    void test(char *str)
    {
    	while(*str != NULL)
    	{
    		cout << *str;
    		str++;
    	}
    }

  5. #5
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    Quote Originally Posted by Quantum1024
    It would be better like this
    Code:
    #include <iostream>
    
    using namespace std;
    
    void test(char *str);
    
    int main ( void )
    {
    	char a[] = "asdf";
    
    	test(a);
    
    	return 0;
    }
    
    void test(char *str)
    {
    	while(*str != NULL)
    	{
    		cout << *str;
    		str++;
    	}
    }
    I honestly don't see anything aside from namespace usage, I apoligize if I'm wrong.

  6. #6
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    That is the only difference. If your going to be using cout a lot then you may as well just use namespace to save having to do stud::cout all the time.

  7. #7
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    Quote Originally Posted by Quantum1024
    That is the only difference. If your going to be using cout a lot then you may as well just use namespace to save having to do stud::cout all the time.

    Ahh thank you, I'm kind of bad on using name spaces, I know I should consider them more often.

    I think all of you for your help

  8. #8
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    Of course you could always just do this with a char pointer.

    Code:
    void test(char *str)
    {
       cout << str;
    
    }

  9. #9
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    i think there are 2 spots in your code
    1) NULL
    pointed 0 instead of NULL
    2) void test(char *str);
    in the case of test would not change the elements which str is refered, void test(const char* str) is better.
    for example
    test("asdf"); it works if the type of parameter is const char*

    at last, i think introducing namespace std into global scope is a bad idea. you can do it like this
    Code:
    void test(const char *str)
    {
                   using namespace std;
    	while(*str != 0)
    	{
    		cout << *str;
    		str++;
    	}
    }
    Nana C++ Library is a GUI framework that designed to be C++ style, cross-platform and easy-to-use.

  10. #10
    *this
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    ^^^ there is nothing wrong with making it global, you make it global so you can use it over and over, doesnt really matter. Ive never seen it used in local scope before.

  11. #11
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    hehe, it's just nothing wrong HERE ^_^, using it in local scope avoids name pollution
    Nana C++ Library is a GUI framework that designed to be C++ style, cross-platform and easy-to-use.

  12. #12
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    I've never seen it used localy either but what jinhao said dose make sense if you intend to use other namespaces which contain conflicting names.

  13. #13
    ATH0 quzah's Avatar
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    i think there are 2 spots in your code
    1) NULL
    pointed 0 instead of NULL
    For all intents and purposes, "NULL" is 0 in C++. Or rather, it is safe to, and indented that you should, use 0 for null comparison in C++.
    Code:
    if( ptr == 0 )
        ...
    Quzah.
    Hope is the first step on the road to disappointment.

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