erlang: Feels like Prolog with actors

Erlang has some similar surface syntax to Prolog:

• Variable , atom
• Pattern matching for function definitions:
  • ; for different patterns
  • , for sequences
  • . for end of statement

Erlang does pattern matching (including unification) on function definition clauses:

fac(0) => 1;
fac(N) => N * fac(N-1).

Actor model:

• Every Process has a mailbox , addressed by it's Pid
  • Pid ! Msg to send a message (returns immediately)
    • Messages arrive in mailbox in order
  • receive function call to process the entire mailbox , looking for a pattern match
    • Messages can be processed in any order
    • Each call to receive can selectively match on any message, each matched is removed, others remain on queue