Re: [sv-ec] class construction syntax - new feature proposal

This comment is a month late, so I have included the original email
at the end for reference.

An alternative syntax would be to use a cast to the desired class type:

	b = C'(new());
	
A cast is equivalent to an assignment to an intermediate variable of the
cast type.  So this would be equivalent to an assignment to an intermediate
variable of type C.  This would indicate that new() should create an
object of type C, since it is assigning to a variable of type C.

It may seem odd to have an assignment that casts to a type other than that
of the LHS.  The cast is the opposite of the actual conversion that is being
done implicitly, from the derived class to the base class.  You could do
that explicitly if it seemed clearer:

	b = B'(C'(new()));



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>From: "Daniel Mlynek" <daniel.mlynek@aldec.com>
>To: <sv-ec@eda-stds.org>
>Subject: [sv-ec] class construction syntax - new feature proposal
>Date: Fri, 5 Sep 2008 09:42:44 +0200
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>X-Received: By mx-sanjose2.Cadence.COM as m857jO52026332 at Fri Sep  5 00:45:24 
2008
>
>There is one annoying thing in object contruction syntax in SV - there is no
>neat and nice way to create an object of user choosen type and assign it to
>handle of different (compatybile type) - consider:
> 
>class B;
>endclass
>class C extends B;
>endclass
> 
>C c;
>B b;
> 
>initial begin
>    c=new;
>    b=c; //I have to write 2 lines of code to create and assign object of
>child type to handle of base type
>//my proposal is to accept syntax: new <class_type_identifier> - which
>always creates an object of pointed type and returns handle to it
>    b = new C;
>end
> 
>I haven't found mantis on it and I cannot see any obsticles to add it to
>LRM.  I've think that this is very usefull - so please consider adding such
>feature.
> 
> 
>DANiel
>
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Steven Sharp
sharp@cadence.com


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