julia> methods(Cairo.set_source_rgb) # 2 methods for generic function "set_source_rgb": set_source_rgb(ctx::CairoContext,r::Real,g::Real,b::Real) at /home/lobi/.julia/v0.3/Cairo/src/Cairo.jl:510 set_source_rgb(gc::GraphicsContext,::Real,::Real,::Real)
and btw: set_source_rgb needs a context as first argument.
