"Folly" is a relatively common English word. "Wangle" is less common but I still see it from time to time.
What I find more interesting than the naming is FB's willingness to remove features from Folly as they are made redundant by Boost or std. I'm unaccustomed to such a lack of arrogance from a major player.
Doesn't removing features break backward compatibility?
My favorite C++ library is Qt; they never remove public API for that reason. In Qt world, we update regularly to get the bug fixes and other features. Last thing I want to do is port my code to some other new API to update the library.
If it's a feature that has made it into the std/Boost libraries, we'll be talking atomic utility functions which are being removed, in favour of calling the std/Boost ones. Not actual API-level features.
What I find more interesting than the naming is FB's willingness to remove features from Folly as they are made redundant by Boost or std. I'm unaccustomed to such a lack of arrogance from a major player.