LÖVE

I've been doing a 2D tile-based platformer game, and I've stumbled across a doubt.

Is there any way of creating a platform (with love.physics) that can be jumped from below, but collides normally from the top?

There should be various ways to implement this. The Box2D manual says it could be done in the pre-solve event where you disable the contact if it's coming from below. I guess a custom collision filter would do it too.