Does Rails 3 have find_by association magic? -

specifically, let's assume have 2 sensible models:

being tiedyecentipede, no 2 legs ever same color. in fact, particular leg's color unique among all of legs of of our tiedyecentipedes.

based on uniqueness, want find particular centipede particular color of leg -- let's :deep_sky_blue.

i like:

critter = leg.find_by_color(:deep_sky_blue).tie_dye_centipede

however, there find_by_* method on tiedyecentipede class use well?

no magic:

tiedyecentipede.joins(:legs).where(:legs => {:color => 'deep_sky_blue'}).first

some magic:

def self.find_by_leg_color(color)   tiedyecentipede.joins(:legs).where(:legs => {:color => color}).first end

Sohocode