def split_prefix(var, prefix)

      if prefix.nil?
        m = VAR_PREFIX_REGEX.match(var.to_s)
        prefix = m[1]
        var = m[2]
      end

      [ var, prefix ]
    end
def split_prefix(var, prefix)

      if prefix.nil?
        m = VAR_PREFIX_REGEX.match(var.to_s)
        prefix = m[1]
        var = m[2]
      end

      [ var, prefix ]
    end
Used by lookup_variable and set_variable to extract the
 prefix in a variable name