Re: array of objects of parametrized constructor

From:

"Alf P. Steinbach /Usenet" <alf.p.steinbach+usenet@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Wed, 04 May 2011 11:42:30 +0200

Message-ID:

<ipr6d0$ihi$1@dont-email.me>

* Ian Collins, on 04.05.2011 11:24:

On 05/ 4/11 09:11 PM, Alf P. Steinbach /Usenet wrote:

* Ian Collins, on 04.05.2011 00:18:

On 05/ 4/11 07:29 AM, Alf P. Steinbach /Usenet wrote:

* asit, on 03.05.2011 20:32:

consider this class

class A
{
     int a;
public:
     A(int x):a(x)
     {
         cout<<"Parametrized constructor"<<endl;
     }
};

How can I create array of objects ??

I can't add the default constructor and overload the parametrized
constructor.

The simplest solution is to use std::vector, from the<vector> header.

E.g.

       std::vector<A> myArray;

       myArray.push_back( A( 1 ) );
       //...

And that's what you should be doing anyway, as a beginner. Don't mess around
with raw arrays. For that matter, don't add assembly language stubs either. ;-)

In this case, using a temporary array as a helper would be fine:

A tmp[] = { 1,2,3,4 };
std::vector<A> a(tmp, tmp+(sizeof(tmp)/sizeof(A)) );

I disagree.

Even an experienced programmer like yourself gets it, well not technically wrong
but pretty imperfect. :-(

If done, it would better look like this:

int const tmp[] = { 1,2,3,4 };
std::vector<A> a(tmp, tmp+(sizeof(tmp)/sizeof(*tmp)) );

You've been secretly reading c.l.c, haven't you Alf??

Sorry, I don't get it.

If you mean c.l.c++ (not the C language group), well I'm an old-timer here. You
should recognize me. I'm one of your humble clc++m moderators, so you can safely
assume that I know a bit of C++ and can cough up original arguments. :-)

Cheers & hth.,

- Alf

--
blog at <url: http://alfps.wordpress.com>