French is kind of planned, that's why we're having this conversation.
For example, the AF is oblivious to https://en.wikipedia.org/wiki/Verlan (unless a word there ends hitting common usage)
> Some verlan words, such as meuf, have become so commonplace that they have been included in the Petit Larousse[3] and a doubly "verlanised" version was deemed necessary, so the singly verlanised meuf became feumeu; similarly, the verlan word beur, derived from arabe, has become accepted into popular culture such that it has been re-verlanised to yield rebeu
This communication, from 2001, on the future of the French language for example http://www.academie-francaise.fr/lavenir-de-la-langue-franca... talks at length about verlan. Just to translate a small excerpt:
A language that stays still is a dying language. Ours is enriching in proportions never seen before. What the 21th century will bring us is verlan. It would be useless to fight it, as oral language has always preceded written language.
I think the Académie is much more competent than many people here think it is.