See the N3242 Working Draft of C++11, chapter 21.5 Numeric Conversions.
There are some useful functions, such as string to_string(int val); mentioned but I don't understand how they're called. Can anyone give me an example please?
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Yakk - Adam Nevraumont
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catfish_deluxe_call_me_cd
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You don't understand how they are called with your compiler or you don't understand how they are called generally? – graham.reeds Sep 22 '11 at 21:19
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My compiler is GNU 4.5.2 and it doesn't "see" them in std:: or anywhere else. Yet they're there in _bits/basic_string.h_. – catfish_deluxe_call_me_cd Sep 22 '11 at 21:21
3 Answers
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Those functions are in the header <string>. You just call them like any other function:
#include <string>
std::string answer = std::to_string(42);
GCC 4.5 already supports those functions, you just need to compile with the -std=c++0x flag.
R. Martinho Fernandes
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Sure:
std::string s = std::to_string(123); // now s == "123"
These functions use sprintf (or equivalent) internally.
Kerrek SB
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2@graham.reeds : No implementation I've seen does, for performance reasons. – ildjarn Sep 23 '11 at 01:23
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They are called like any other function:
int number = 10;
std::string value;
value = std::to_string(number);
std::cout << value;
To call them you will need a C++ compiler that supports the draft recommendations (VS2010 and GCC4+ I think support them).
graham.reeds
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@catfish_deluxe_call_me_cd no, you don't need to upgrade. You must be doing something wrong. – R. Martinho Fernandes Sep 22 '11 at 21:28
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I know this isn't a tech support forum but does anyone else use MinGW to test for this? – catfish_deluxe_call_me_cd Sep 23 '11 at 09:05