Loops, optional destructive assignment, tabling (although some Prolog implementations also have tabling), better constraint programming support than many Prolog implementations.
With version 3.0 Picat is also mostly backward-compatible with Prolog.
With version 3.0 Picat is also mostly backward-compatible with Prolog.
In my opinion, Picat's biggest attraction is its facilities for constraint solving and optimization, which are in some respects state of the art.