# File lib/compass/commands/registry.rb, line 12
    def abbreviation_of(name)
      re = /^#{Regexp.escape(name)}/
      matching = @commands.keys.select{|k| k.to_s =~ re}
      if matching.size == 1
        matching.first
      elsif name =~ /^-/
        nil
      elsif matching.size > 1
        raise Compass::Error, "Ambiguous abbreviation '#{name}'. Did you mean one of: #{matching.join(", ")}"
      else
        raise Compass::Error, "Command not found: #{name}"
      end
    end