One selling point of Vibe.d is its Support for graphical user interfaces.
So far, I can't fancy a decent use case leveraging this feature and would be very pleased if someone can tell more about it.
Anything related to (Twitter) Stream API for instance?!
I'm just asking for one example to get started and limit the scope of this post.
Here's what the documentation says: http://vibed.org/features#productivity
Graphical user interface integration
Contrary to most other frameworks supporting asynchronous I/O, vibe.d fully integrates with the UI event loop, so that it can be used to power applications with a graphical user interface.
For Windows, there is a native event driver implementation (enable with VibeWin32Driver) that makes use of the MsgWaitForMultipleObjectsEx function to process window messages together with I/O or concurrency events. For systems running X11, it's possible to use createFileDescriptorEvent to listen on the display connection instead of using XNextEvent.
I haven't used vibe.d so I'm not really authorative on this, but I have written similar code before so that description tells me my experience surely applies.
When you are writing a GUI program, one of the difficulties can be remaining responsive to user inputs (window events) while using custom events too - many frameworks do their own event loop to respond to data-ready messages and the GUI application needs an event loop too to respond to stuff like mouse-clicked messages.
vibe.d can use one event loop for both, just meaning you can use its async I/O features while handling window messages without needing a separate GUI thread and without blocking on a message mucking up I/O.
I guess a concrete example might be a server application with a control+stats window visible for the administrator.
The case I looked into similar code for was handling console input, GUI input, and network input writing a network enabled terminal emulator. I had to handle incoming ssh packets, key presses, and abort input from the parent terminal all without blocking.
