Free/Shareware Prolog implementations

lang/prolog/impl/

   clp/       Constraint Logic Programming implementations
   fp_lp/     Implementations of Functional/Logic Programming 
              Languages
   lp/        Logic programming language implementations other 
              than Prolog.
   other/     Other logic-related languages of interest.
   parallel/  Free/Shareware Parallel Prolog implementations
   prolog/    Free/Shareware Prolog implementations
   wam/       WAM: WAM emulators and tracers.