# like `lookup_all_values` but return a big concatenated sequence (instead of a sequence of array)
	fun lookup_joined_values(mmodule: MModule, min_visibility: MVisibility): Sequence[E]
	do
		var mmodules = lookup_all_modules(mmodule, min_visibility)
		mmodules = model.mmodule_importation_hierarchy.linearize(mmodules)
		var res = new Array[E]
		for m in mmodules do res.add_all defs[m]
		return res
	end