hphpd> =Facebook\HackRouter\PrefixMatching\PrefixMap::fromFlatMap(dict(keyset['foo', 'herp/foo/{abc}', 'herp/bar/{def}', 'herp/baz/{ghi}', 'herp/derp/foo/{abc}', 'herp/derp/baz/{abc}']))->getSerializable()
Dict
(
    [literals] => Dict
        (
            [foo] => "foo"
        )

    [prefixes] => Dict
        (
            [herp/foo/] => Dict
                (
                    [regexps] => Dict
                        (
                            [#(?<abc>[^/]+)#] => "herp/foo/{abc}"
                        )

                )

            [herp/bar/] => Dict
                (
                    [regexps] => Dict
                        (
                            [#(?<def>[^/]+)#] => "herp/bar/{def}"
                        )

                )

            [herp/baz/] => Dict
                (
                    [regexps] => Dict
                        (
                            [#(?<ghi>[^/]+)#] => "herp/baz/{ghi}"
                        )

                )

            [herp/derp] => Dict
                (
                    [prefixes] => Dict
                        (
                            [/foo/] => Dict
                                (
                                    [regexps] => Dict
                                        (
                                            [#(?<abc>[^/]+)#] => "herp/derp/foo/{abc}"
                                        )

                                )

                            [/baz/] => Dict
                                (
                                    [regexps] => Dict
                                        (
                                            [#(?<abc>[^/]+)#] => "herp/derp/baz/{abc}"
                                        )

                                )

                        )

                )

        )

)