\ LOOK.FS xt -> lfa 22may93jaw
\ Copyright (C) 1995 Free Software Foundation, Inc.
\ This file is part of Gforth.
\ Gforth is free software; you can redistribute it and/or
\ modify it under the terms of the GNU General Public License
\ as published by the Free Software Foundation; either version 2
\ of the License, or (at your option) any later version.
\ This program is distributed in the hope that it will be useful,
\ but WITHOUT ANY WARRANTY; without even the implied warranty of
\ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
\ GNU General Public License for more details.
\ You should have received a copy of the GNU General Public License
\ along with this program; if not, write to the Free Software
\ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
\ Look checks first if the word is a primitive. If yes then the
\ vocabulary in the primitive area is beeing searched, meaning
\ creating for each word a xt and comparing it...
\ If a word is no primitive look searches backwards to find the nfa.
\ Problems: A compiled xt via compile, might be created with noname:
\ a noname: leaves now a empty name field
\ >NAME PRIMSTART 22may93jaw
\ : >name ( xt -- nfa )
\ BEGIN 1 chars -
\ dup c@ 128 and
\ UNTIL ;
: PrimStart ['] true >name ;
\ look 17may93jaw
: (look) ( xt startlfa -- lfa flag )
BEGIN @ dup
WHILE dup name>
3 pick = IF nip dup THEN
dup 0<> ;
: look ( cfa -- lfa flag )
dup forthstart <
IF PrimStart (look)
ELSE >name true THEN ;