2 const cell
: cells cell * ;

key ) const ')'

10 const '\n'
key  const sp

128 const F_IMMEDIATE

: cr '\n' emit ;
: bl sp emit ;

: if ' BZ_ , here 0 , ; immediate
: else ' GOTO_ , 0 , here swap ! here cell - ; immediate
: then here swap ! ; immediate

: begin here ; immediate
: while ' BZ_ , here 0 , ; immediate
: repeat ' GOTO_ , swap , here swap ! ; immediate
: again ' GOTO_ , , ; immediate
: until ' BZ_ , , ; immediate

: ( begin key ')' = until ; immediate
: lit ' LIT_ , , ;

: interpretword F_IMMEDIATE & state not or if execute else , then ;
: interpretnumber state if lit then ;
: interpretunknown type s" ?" type cr ;
: compileword lookup dup
    if interpretword
    else drop number
      if interpretnumber
      else interpretunknown
      then
    then ;
: interpreter
  begin word dup b@ while compileword repeat drop ;
: load-input swap-input r> r> interpreter r< r< swap-input ;
: loadstring ' key-string load-input drop drop ;
: loadfile ' key-file load-input drop close ;