module Phlex::Collection

def initialize(collection: nil, item: nil)
	unless collection || item
		raise ArgumentError, "You must pass a collection or an item as a keyword argument."
	end
	@collection = collection
	@item = item
end

def template
	@item ? item_template : collection_template { yield_items }
end

def yield_items
	if @item
		raise ArgumentError, "You can only yield_items when rendering a collection. You are currently rendering an item."
	end
	@collection.each do |item|
		@item = item
		item_template
	end
	@item = nil
end