úÎ • +A type for Uniform Unique Identifiers. The  instance allows s  to be specified with 0, 1, &c. -- testing for the null  is  easier that way. The ) instance is compatible with most (all?)  systems' native representation of s. JAllocates a pointer to capture the output of a foreign function, runs the O function and interprets the sixteen bytes following the pointer as a UUID. Obtain a Version 4 UUID with the native UUID generator. Obtain a Version 1 UUID with the native UUID generator.        system-uuid-2.0.0 Data.UUIDSystem.UUID.FromForeignSystem.UUID.V4System.UUID.V1UUID runAndReaduuidbaseGHC.NumNumForeign.StorableStorablenative