factor/library/continuations.factor

32 lines
913 B
Factor

! Copyright (C) 2003, 2005 Slava Pestov.
! See http://factor.sf.net/license.txt for BSD license.
IN: kernel USING: errors lists namespaces sequences words ;
TUPLE: interp data call name catch ;
: interp ( -- interp )
datastack callstack >pop> >pop>
namestack catchstack <interp> ;
: continuation ( interp -- )
interp dup interp-call >pop> >pop> drop
dup interp-data >pop> drop ;
: >interp< ( interp -- data call name catch )
[ interp-data ] keep
[ interp-call ] keep
[ interp-name ] keep
interp-catch ;
: set-interp ( interp quot -- )
>r >interp< set-catchstack set-namestack
>r set-datastack r> r> swap set-callstack call ;
: callcc0 ( quot ++ | quot: cont -- | cont: ++ )
continuation
[ [ ] set-interp ] cons swap call ;
: callcc1 ( quot ++ obj | quot: cont -- | cont: obj ++ obj )
continuation
[ swap literalize unit set-interp ] cons swap call ;