ggplot2/R/scale-.r Lines 1185 to 1191 inaaaec2f type<-if(name=="position_b") { "binned" }elseif(name=="position_c") { "continuous" }else{ "discrete" } It think an alternative might be to consider to use theinherits(scale, "ScaleContinuous")pattern above (which should beTRUEfor...