RE: [Dev-C++] Derived class initialization

[Schedler, K. <Kur...@hi...>]

when you construct a derived class, the parent class is fully constructed
first, then the derived class is constructed.  in this case, the baseclass
constructor requires three arguments.  in order for the baseclass to be
constructed properly, it needs to receive its arguments immediately.  the
colon begins what is called a function preamble.  This allows you to
construct base classes and initialize constant data members before
performing the body of your constructor.  all this code really means to you
is "before we construct our derived class, we need to construct the base
class".
 
the author of "C++ In Action" ( http://www.relisoft.com/book/index.htm)
<http://www.relisoft.com/book/index.htm)>  makes extensive use of function
preambles for setting variables and whatnot.

-----Original Message-----
From: softnasolutions-ltd.fsbusiness.co.uk
[mailto:so...@so...]
Sent: Monday, June 25, 2001 10:54 AM
To: dev...@li...
Subject: [Dev-C++] Derived class initialization


Hi all,
I'm stuying C++ using some sample programs and I have come accross this line
of code which i don't quite understand. PLease sombody tell me what it
means.
 
derivedclass::derivedclass(classgrade *ave, name, age) : baseclass(ave,
name, age).
 
What i don't understand is what it means to have :baseclass(ave, name, age).
I figure it has something to do with initiallising the derived calss. but i
don't understant exactly what it does.
 
Thnx.
 
Napoleon.



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