The problem is that most examples or projects will work on multiple platforms either directly or with a simple change of pin numbers at the start. That is the whole point of the mbed libraries.
So in order for the filter to work in a way that would be useful for a wide range of people each project would have to have a list of supported platforms rather than a single platform associated with it.
You would then have to rely on the person creating the library to correctly indicate all of the supported platforms which they may not know and almost certainly don't have on hand to test against. Also everything would need updating every time a new platform was added.
A far simpler and more robust solution if somewhat more manual would be to allow user created sub folders so that you can have an examples folder that you can then subdivide by platform, category, day of the week you found it or any other criteria you wish to make up.
That feature already has a thread on this board requesting it.
Is there any way I can link my program workspace to my selected platform. One would think this is something that can be automated or offered as an option to the user. This will ensure that once I select the platform I want to program only those program examples and libraries, which are valid to that platform, will show up on my program workspace.
At the moment I have to manually go through and check which example program, which I had previously downloaded as useful reference, is valid or not. This is time consuming now that I now develop on multiple boards / platforms and have loads of different examples / libraries downloaded. It is rather congested and messy.