Re: Creating a block using the Macros....

I kind of figured.   This means that some of the functionality of classes that I have added lately will not be usable to people using GCC based builds.  I have been wondering, lately, when GCC will catch up or if we should, at some point, deprecate it's use with GNUstep since it only serves to complicate matters.

GC

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On Tue, Oct 29, 2019 at 8:42 AM David Chisnall <address@hidden> wrote:

This is not possible in the general case.

A block is a structure containing:

- A pointer to the invoke function.
- The type info for the call.
- A set of references to captured variables including:
- Helpers to destroy any captured variables.
- Helpers to copy any captured variables.

C macros are nowhere near expressive enough for this. You could
probably (just about) implement them using C++ templates, though it
would be a lot of work.

The block macros give a way of allowing functions / methods that take
blocks to be called, so that it is possible to build GNUstep with GCC
and link it to a program built with clang. To date, anything that needs
to create blocks, we have implemented a different way or conditionally
compiled out when building with GCC.

David

On 27/10/2019 15:55, Gregory Casamento wrote:
> How do I create a block using the macros? I know how to declare one,
> but not actually create one. Doing it in clang is easy, but I need
> something that will work for both....
>
> Any ideas?
>
> GC
> --
> Gregory Casamento
> GNUstep Lead Developer / OLC, Principal Consultant
> http://www.gnustep.org - http://heronsperch.blogspot.com
> http://ind.ie/phoenix/
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From:	Gregory Casamento
Subject:	Re: Creating a block using the Macros....
Date:	Thu, 31 Oct 2019 19:53:52 -0400