Array of references

[resumurof]

Hello Guys,

why array of references are not allowed,can anyone give me explanation on this.

thanks in advance

[Lindley]

Because the standard does not require a reference to have a size in memory, and array elements must have a defined size.

In practice most compilers implement references as pointers, which have a size, but there are other possibilities.

[resumurof]

I have a sample program created for array of references, it works fine.

void main()
{

cout << endl << endl << "Values in nArray2 when referenced" << endl;

int pnArray2[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

int (&array_ref)[ 10 ] = pnArray2;

for(int i=0;i < 10; i++)
{


cout << array_ref[i] << endl;
}

}

[ninja9578]

Some compilers support other things that are not in the standard, GNU seems to allow arrays of references. Another example of compiler specific functionality is your main method. G++ wont compile unless main returns int.

[Lindley]

I have a sample program created for array of references, it works fine.

I believe that's a reference to an array, not an array of references.

[Moschops]

Looks like an array of ints to me, not an array of references. What happens if you try to make an array of references to ints, like this?

&int pnArray2[10];

[monarch_dodra]

void main()

That's int main() !

Looks like an array of ints to me, not an array of references. What happens if you try to make an array of references to ints, like this?

&int pnArray2[10];

Yes. The correct syntax to incorectly create an array of references is:

    int &(array_ref[10]) = ...;
or
    int &array_ref[10] = ...;

Both of which are diagnosed as:

error: declaration of 'array_ref' as array of references

[Paul McKenzie]

I have a sample program created for array of references,

    int (&array_ref)[ 10 ] //...

When was the last time you coded an array declared like that, with all of those parentheses? Probably never. Wouldn't this be much easier?

int &array_ref[10];

But this doesn't compile, so this means that there is no such thing as an "array of references". This is from the on-line Comeau compiler:

Thank you for testing your code with Comeau C/C++!
Tell others about http://www.comeaucomputing.com/tryitout !

Your Comeau C/C++ test results are as follows:

Comeau C/C++ 4.3.10.1 (Oct  6 2008 11:28:09) for ONLINE_EVALUATION_BETA2
Copyright 1988-2008 Comeau Computing.  All rights reserved.
MODE:strict errors C++ C++0x_extensions

"ComeauTest.c", line 12: error: array of reference is not allowed
  int &array_ref[ 10 ] = pnArray2;

Your original declaration is not an "array of references". It is a single reference to an array of 10 integers. If you tried to assign an array with a different number of ints, you get an error.

Regards,

Paul McKenzie

[Zaccheus]

why array of references are not allowed

You cannot take the address of a reference, but arrays in C++ are really just pointers to the first element of an array.