1:      1  1 CALL pred interpreter:main/2-0 (det) 
mdb> echo on
Command echo enabled.
mdb> register --quiet
mdb> 10 step
Pure Prolog Interpreter.

Consulting file `interpreter.m'...
      11:      6  5 SWTC pred interpreter:consult_until_eof_2/5-0 (det) s3;
mdb> vars
        1 HeadVar__1
        2 HeadVar__2
        3 HeadVar__4
mdb> print *
       HeadVar__1             	term(varset(var_supply(0), empty, empty), functor(atom(":-"), .(functor/3, []), context("interpreter.m", 22)))
       HeadVar__2             	[]
       HeadVar__4             	state('<<c_pointer>>')
mdb> goto 30
      30:     16 12 CALL pred interpreter:database_assert_clause/4-0 (det) 
mdb> print *
       HeadVar__1             	.(clause(varset(var_supply/1, empty, empty), functor(atom/1, ./2, context/2), functor(atom/1, [], context/2)), .(clause(varset/3, functor/3, functor/3), .(clause/3, [])))
       HeadVar__2             	varset(var_supply(0), empty, empty)
       HeadVar__3             	functor(atom(":-"), .(functor(atom/1, ./2, context/2), []), context("interpreter.m", 26))
mdb> finish -a
      31:     16 12 ELSE pred interpreter:database_assert_clause/4-0 (det) e;
      32:     16 12 EXIT pred interpreter:database_assert_clause/4-0 (det) 
mdb> print *
       HeadVar__1             	.(clause(varset(var_supply/1, empty, empty), functor(atom/1, ./2, context/2), functor(atom/1, [], context/2)), .(clause(varset/3, functor/3, functor/3), .(clause/3, [])))
       HeadVar__2             	varset(var_supply(0), empty, empty)
       HeadVar__3             	functor(atom(":-"), .(functor(atom/1, ./2, context/2), []), context("interpreter.m", 26))
       HeadVar__4             	.(clause(varset(var_supply/1, empty, empty), functor(atom/1, ./2, context/2), functor(atom/1, [], context/2)), .(clause(varset/3, functor/3, functor/3), .(clause/3, ./2)))
mdb> 
      33:     17 12 CALL pred interpreter:consult_until_eof/4-0 (det) 
mdb> finish -n
     677:     17 12 EXIT pred interpreter:consult_until_eof/4-0 (det) 
mdb> 
     678:     15 11 EXIT pred interpreter:consult_until_eof_2/5-0 (det) 
mdb> 
     679:     14 10 EXIT pred interpreter:consult_until_eof/4-0 (det) 
mdb> continue
?-