This tense is in the future, and it is perfect. Let's first define those two terms. Future of course means happening after now. One minute from now/ tomorrow/ in 6 years/ etc. The 'official' definition of 'future' is... a period of time following the moment of speaking or of writing/ time considered as still to come. What about 'perfect'? In grammar, what does it mean?
Well, perfect, in grammar, refers to a verb that was, is or will be complete at the moment under consideration. Here's a good general French definition of perfect: Nous utilisons le parfait pour revenir sur un moment précis et parler de ce qui s'est passé jusqu'à ce moment-là ou de ce qui est important à ce moment-là.
Aujourd'hui, nous nous concentrons sur le futur parfait, dans lequel à un moment donné dans le futur, une action aura fini, ou se sera arrêtée, ou aura été faite.
A PERIOD FOLLOWING THE MOMENT OF SPEAKING + WHAT WILL BE COMPLETE AT A MOMENT IN THE FUTURE
Tomorrow at 3pm + we will have finished the project.
The storm will have stopped + by the time we arrive.
I can come out tonight. + I'll have finished my meeting by then.
FORMULA: To indicate the future perfect tense, we use will + have + verb (past participle).
Here are some more examples:
- I will have slept eight hours when you arrive. [J'aurai dormi huit heures quand tu arriveras.]
- When the match begins, she will have finished the book. [Lorsque le match commencera, elle aura terminé le livre.]
- He'll have spent all his money in June next year. [Il aura dépensé tout son argent en juin de l'année prochaine.]