Declare array then assign with a comma seperated list

I know I can do this:

Code:

int a[4] = {1,2,3,4};

but I want to do this:

Code:

int a[4];
a = {1,2,3,4};

What is this called and what version of gcc do I need?

Thanks!

It is called a brace-enclosed-extended-initializer-list ! (seriously)
Though primitive arrays are not supported, unfortunately. But most STL containers are.
Here is an example.

Code:

#include<vector>
int main()
{
    std::vector<int> foo;
    foo = {1,2,3,4,5};
}

It works for me, with gcc 4.7.2.

Though primitive arrays are not supported, unfortunately.

Then again, it seems rather odd that you would completely construct foo and then assign the values of foo to it, with an initializer list. That's not how initialization is supposed to work. So, you could argue that the language always has supported this for arrays.

Originally Posted by whiteflags

Then again, it seems rather odd that you would completely construct foo and then assign the values of foo to it, with an initializer list. That's not how initialization is supposed to work. So, you could argue that the language always has supported this for arrays.

What if you want to replace the whole set of data at once ?
This would look and behave better than constructing another vector and swapping.

How is that not what happens, anyway?

Originally Posted by whiteflags

How is that not what happens, anyway?

You have a point..

Thanks guys. Weird thing is that mingw will compile:

Code:

int a[4];
a = {1,2,3,4};

but gcc 4.7 won't. Is there a bug with mingw that is allowing me to do this?

Related thread
Brace-enclosed initializer list in an assignment


Message I got on unofficial TDM MinGW g++ 4.7.? build

Code:

main.cpp|7|warning: extended initializer lists only available with -std=c++11 or -std=gnu++11 [enabled by default]|

After doing either -std=c++11 or -std=gnu++11 I still get this error.

Code:

main.cpp:7:17: error: assigning to an array from an initializer list

Tim S.

Originally Posted by stahta01

Related thread
Brace-enclosed initializer list in an assignment


Message I got on unofficial TDM MinGW g++ 4.7.? build

Code:

main.cpp|7|warning: extended initializer lists only available with -std=c++11 or -std=gnu++11 [enabled by default]|

After doing either -std=c++11 or -std=gnu++11 I still get this error.

Code:

main.cpp:7:17: error: assigning to an array from an initializer list

Tim S.

lol gcc > mingw