Runtime guard: is this a live functype Serializable? Checks for the
serialize() method plus the _tag field that every Serializable instance
carries. Use this when wrapping serialize/deserialize in a host
serializer that needs to distinguish functype values from foreign data
(e.g. isApplicable in a DBOS recipe).
Runtime guard: is this a live functype Serializable? Checks for the
serialize()method plus the_tagfield that every Serializable instance carries. Use this when wrappingserialize/deserializein a host serializer that needs to distinguish functype values from foreign data (e.g.isApplicablein a DBOS recipe).