def processHrefSubstitutions(hrefs, prefix):
    """
    Process the list of hrefs by prepending the supplied prefix. If the href is a
    list of hrefs, then prefix each item in the list and expand into the results. The
    empty string is represented by a single "-" in an href list.

    @param hrefs: list of URIs to process
    @type hrefs: L{list} of L{str}
    @param prefix: prefix to apply to each URI
    @type prefix: L{str}

    @return: resulting list of URIs
    @rtype: L{list} of L{str}
    """

    results = []
    for href in hrefs:
        if href.startswith("["):
            children = href[1:-1].split(",")
            results.extend([(prefix + (i if i != "-" else "")).rstrip("/") for i in children if i])
        else:
            results.append((prefix + href).rstrip("/"))

    return results