defining and instantiate class at once

Question

i just found out we can defining and instantiate class at once like this

#include <iostream>

using namespace std;

class PLAYERS
{
public:
    int value3;
    PLAYERS(int value3)
    {
        this->value3 = value3;
    }
}play1(2), play2(3), play3(7);

int main()
{
    play1.value3 = 2;
    PLAYERS play4();
    cout << "Hello world!" << endl << play1.value3;
    return 0;
}

what is it called? when i delete the argument on instantiation of play1, play2, play3 like play4. it will compile error but the play4 is fine. how it can be?

Maybe split this into two questions? The `play4()` one is a duplicate. — juanchopanza, Dec 07 '16 at 07:27
@StoryTeller ah yes, stupid me, i intend to call default constructor but i'm forgot to call default constructor must be not use parenthesis or it will be function declaration and i laugh at myself because there is no default constructor in that class haha.. after i fix the code it compiles fine, just my mistake. thank you — Aorstab, Dec 07 '16 at 08:01
@juanchopanza yes i will edit it, maybe i will delete the second question. if i may can you post the link of that same question? — Aorstab, Dec 07 '16 at 08:01
downvoted. please dont modify the whole question,after solving it, just because you are lazy to create a new thread. this will be confusing to the future researcher. — Lorence Hernandez, Dec 07 '16 at 08:05

score 0 · Accepted Answer · answered Dec 07 '16 at 08:49

It's just called multiple declarations, no special name as far as I'm aware.

You're just making use of a shortened way of doing so, by having the declarations between the closing brace of the class definition and the semi-colon, which is perfectly valid but unusual.

defining and instantiate class at once

1 Answers1