Programming Forums > Application Development > C++

monkey8 · Nov 19th, 2004, 11:47 AM

When you use

using namespace std;

It includes the whole std namepace. Try using just what you need

(Toggle Plain Text)

using std::cout;
using std::cin;

and see if that reduces executable size.

Ooble · Nov 19th, 2004, 3:08 PM

Eh? I always assumed that just enabled you to use elements of a template without having to type its name each time. The space is taken up with this line: #include <iostream>.

Eggbert · Nov 19th, 2004, 4:07 PM

>I always assumed that just enabled you to use elements of a template without having to type its name each time.
It makes every name in the namespace visible in the global namespace without qualification. The names don't have to be templates.

>The space is taken up with this line: #include <iostream>.
Yes. The using directive only deals in visibility; it's the dependencies of the header that will effect file size. For example, if iostream also included fstream, string, and cstdlib then the translation unit size would be equivalent to the sum union of all of the header sizes. Also, the static library referenced by each header would be linked into the executable and the size would reflect that.

A well written library will minimize dependencies to speed up compilation and shrink translation unit and executable file sizes, but not all standard library implementations are that good.

Dia_Byte · Nov 20th, 2004, 10:11 AM

well all these are good sugestions that i intend to try one by one to have the best benefit of C++

its confusing how a famous language like this can cause much trouble :blink:

Eggbert · Nov 20th, 2004, 10:32 AM

>its confusing how a famous language like this can cause much trouble
Quality of implementation issues exist everywhere. It's most evident with languages like C and C++ that are very popular and have many different implementations of the standard language (both open source and retail). If you can't find a way around the problem then complain to the vendor. Header dependencies are their mistake and they should fix it. You shouldn't have to switch from C++ to C just to get smaller binaries.

Dia_Byte · Nov 25th, 2004, 9:00 AM

well i'm really thinking about mailing DEV_CPP creators maybe they'lle find a sollution !

Nov 19th, 2004, 11:47 AM	#21
monkey8 Newbie Join Date: Nov 2004 Posts: 12 Rep Power: 0	When you use (Toggle Plain Text) using namespace std; using namespace std; It includes the whole std namepace. Try using just what you need (Toggle Plain Text) using std::cout; using std::cin; using std::cout; using std::cin; and see if that reduces executable size.

Nov 19th, 2004, 3:08 PM	#22
Ooble I eat cake for breakfast. Join Date: Jul 2004 Location: In my box. Posts: 4,434 Rep Power: 9	Eh? I always assumed that just enabled you to use elements of a template without having to type its name each time. The space is taken up with this line: #include <iostream>. __________________ Me :: You :: Them

Nov 20th, 2004, 10:11 AM	#24
Dia_Byte Programmer Join Date: Nov 2004 Location: Bierut - Lebanon Posts: 34 Rep Power: 0	well all these are good sugestions that i intend to try one by one to have the best benefit of C++ its confusing how a famous language like this can cause much trouble :blink: __________________ <removed by Administrator>

Nov 25th, 2004, 9:00 AM	#26
Dia_Byte Programmer Join Date: Nov 2004 Location: Bierut - Lebanon Posts: 34 Rep Power: 0	well i'm really thinking about mailing DEV_CPP creators maybe they'lle find a sollution ! __________________ <removed by Administrator>

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Nov 19th, 2004, 4:07 PM	#23
Eggbert Professional Programmer Join Date: Nov 2004 Posts: 250 Rep Power: 4	>I always assumed that just enabled you to use elements of a template without having to type its name each time. It makes every name in the namespace visible in the global namespace without qualification. The names don't have to be templates. >The space is taken up with this line: #include <iostream>. Yes. The using directive only deals in visibility; it's the dependencies of the header that will effect file size. For example, if iostream also included fstream, string, and cstdlib then the translation unit size would be equivalent to the sum union of all of the header sizes. Also, the static library referenced by each header would be linked into the executable and the size would reflect that. A well written library will minimize dependencies to speed up compilation and shrink translation unit and executable file sizes, but not all standard library implementations are that good.

Nov 20th, 2004, 10:32 AM	#25
Eggbert Professional Programmer Join Date: Nov 2004 Posts: 250 Rep Power: 4	>its confusing how a famous language like this can cause much trouble Quality of implementation issues exist everywhere. It's most evident with languages like C and C++ that are very popular and have many different implementations of the standard language (both open source and retail). If you can't find a way around the problem then complain to the vendor. Header dependencies are their mistake and they should fix it. You shouldn't have to switch from C++ to C just to get smaller binaries.

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Programming Forums > Application Development > C++

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