NetNews Usenet Archive 1992 #30/NN_1992_30.iso/spool/comp/lang/cplus/17840

Text File | 1992-12-11 | 1.4 KB | 61 lines

Newsgroups: comp.lang.c++
Path: sparky!uunet!spool.mu.edu!umn.edu!csus.edu!borland.com!pete
From: [e-mail] (Pete Becker)
Subject: Re: Complex Addition.
Message-ID: <[e-mail]>
Originator: [e-mail]
Sender: [e-mail] (News Admin)
Organization: Borland International
References: <[e-mail]>
Date: Fri, 11 Dec 1992 23:29:54 GMT
Lines: 48

In article <[e-mail]> [e-mail] (Guy Pickering) writes:
>In ARM, the code for the `+` operator for the complex class is given as:
>
>inline complex operator+(complex a, complex b)
>{
>  return complex(a.re+b.re,a.im+b.im)
>}
>
>In general, can I create an instance of a class in a member function and
>return the object? Doesn't the complex object go out of scope?
>

    Yes, it does.  But that's not the end of the inquiry.

    int add( int a, int b )
    {
    return a+b;
    }

    Here, too, the temporary goes out of scope, but the compiler knows how
to deal with that.  Same thing for an object of a user-defined type.

>Could I do this:
>
>SomeClass operator<<(SomeClass data, int places)
>{
>  SomeClass temp(data);        // Copy data to temporary object.
>
>  // manipulate temp internally to perform
>  // the << operation.
>
>  return temp;
>}
>
>Would this allow me to write:
>
>  value1 = value2 << 5;
>
>If both variables were of type SomeClass?
>

    Yes.

    -- Pete