      <p>The present SRFI proposes an extensible
      external representation of Scheme values, a notational convention for
      future SRFIs. This SRFI adds <code>#,(</code> as a new token and extends
      production rules of the grammar for a Scheme reader. The
      <code>#,()</code> form can be used for example to denote values that do
      not have a convenient printed representation, as well for conditional
      code compilation. It is proposed that future SRFIs that contain new read
      syntax for values use the <code>#,()</code> notation with an appropriate
      tag symbol.
      <p>As a particular example and the reference
      implementation for the <code>#,()</code> convention, this SRFI describes
      an interpretation of the <code>#,()</code> external form as a read-time
      application.