4.1 one_bit_full_adder

The first block, one_bit_full_adder is a straightforward implementation of the classic full-adder (see truth table).

     ;;; One-bit full-adder.
     
     ; a b c_in   c_out sum
     ; 0 0 0          0 0
     ; 0 0 1          0 1
     ; 0 1 0          0 1
     ; 0 1 1          1 0
     ; 1 0 0          0 1
     ; 1 0 1          1 0
     ; 1 1 0          1 0
     ; 1 1 1          1 1
     
     (blk one_bit_full_adder
          (out       c_out)
          (out       s)
          (in        a)
          (in        b)
          (in        c_in))
     
     (a. s     (^ a b c_in))
     (a. c_out (| (& a c_in)
                  (& a b)
                  (& b c_in)))