Use different parameter data types in same function? (C++)

Question

So say I had:

public: static void print(string message) { }

Is there a way I could make it accept other data types (eg. int, double etc) in the same function? So I could call it like print(7) and it would work?

Thanks everyone for the answers; in the title I wanted it as the same function because I didn't realise functions could have the same names as each other (like variables). Hence, I thought the only way you could do it was through the same function. As I am quite new to C++, I preferred the method of just using the same function name and doing it with different parameters (the overloading method).

@user2672165 Overloading is for reusing the name, not the "same function". I presume OP meant the same code, to avoid copying statements, that would make sense. Though, on the second thought I might be wrong. — luk32
– luk32, Commented Dec 29, 2014 at 11:22
@luk32 Overloading seems fine to me. I didn't think that you could have functions with the same name (like variables) so I thought the only option would be to have it in the same function. — Jay
– Jay, Commented Dec 29, 2014 at 11:52

luk32 · Accepted Answer · 2014-12-29 11:25:37Z

1

This is what the templates are for e.g:

template<typename Type>
void print_something(Type something) {
  std::cout << something << '\n';
}

The compiler is smart enough to deduce type from parameter. So you can call it like this:

print_something("test");
print_something(42);

It also works for member functions. What compiler does is it substitutes the Type with a concrete type (like int, or char*, or std::string) and produces an overload.

edited Dec 29, 2014 at 11:25

answered Dec 29, 2014 at 11:20

luk32

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FelipeDurar · Accepted Answer · 2014-12-29 11:44:24Z

0

just create functions with the same name but with different parameters, this is called function overload, for example:

void print(char *message) { printf("%s", message); }
void print(int val) { printf("%d", val); }
void print(char ch) { printf("%c", ch); }

All above functions are overloaded, see examples of calling:

print("Hello World!");
print(10);
print('P');

this is only available in C++ (not in C)

answered Dec 29, 2014 at 11:44

FelipeDurar

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1 Comment

Jay Over a year ago

Thanks, didn't realise functions could have the same name.

smali · Accepted Answer · 2014-12-29 11:22:41Z

0

You can use C++ templates, Template provide generic data types in c++. see this for more details.

http://www.tutorialspoint.com/cplusplus/cpp_templates.htm http://www.cprogramming.com/tutorial/templates.html

answered Dec 29, 2014 at 11:22

smali

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Sdghasemi · Accepted Answer · 2014-12-29 11:29:02Z

0

You can easily do that by using templates. like this:

template <class T>
class CTest{
    .
    .
    .
}
template <class T>
static void print::CTest<T>(T message){...}

and then specify your variable type while using in your main function.

answered Dec 29, 2014 at 11:29

Sdghasemi

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