module Phlex::Helpers

def tokens(*tokens, **conditional_tokens)
	conditional_tokens.each do |condition, token|
		case condition
		when Symbol then next unless send(condition)
		when Proc then next unless condition.call
		else raise ArgumentError,
			"The class condition must be a Symbol or a Proc."
		end
		case token
		when Symbol then tokens << token.name
		when String then tokens << token
		when Array then tokens.concat(token)
		else raise ArgumentError,
			"Conditional classes must be Symbols, Strings, or Arrays of Symbols or Strings."
		end
	end
	tokens.compact.join(" ")
end