def link_to_changes_in_release(release, releases):
    """
    Markdown text for a hyperlink showing all edits in a release, or empty string

    :param release: A release version, as a string 
    :param releases: A container of releases, in descending order - newest to oldest
    :return: Markdown text for a hyperlink showing the differences between the give release and the prior one,
             or empty string, if the previous release is not known
    """

    if release == releases[-1]:
        # This is the earliest release we know about
        return ''
    index = releases.index(release)
    previous_release = releases[index + 1]
    return '\n[Changes in %s](https://github.com/catchorg/Catch2/compare/v%s...v%s)' % (release, previous_release, release)