be all for something/for doing something
be (all) for (someone or something)
To support or be in favor of a person, group, or effort. If management is considering adding a gym to the building, I'm all for it! I respect your opinion, but I'm for the other candidate. I don't know about the rest of you, but I'm all for going on a hike!
See also: for
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
be all for something/for doing somethingbelieve strongly that something should be done: They’re all for saving money where they can. OPPOSITE: be (dead) set against something/against doing something
Farlex Partner Idioms Dictionary © Farlex 2017