File:  [gforth] / gforth / Attic / search-order.fs
Revision 1.6: download - view: text, annotated - select for diffs
Thu Aug 25 15:25:34 1994 UTC (29 years, 7 months ago) by anton
Branches: MAIN
CVS tags: HEAD
make now generates both images
the image names were changed
added C-level support for deferred words (dodefer)
made 2>r 2r> 2r@ 2rdrop primitives
some tuning of the outer interpreter; eliminated many words based on
 counted strings
Replaced the hash function with one that works better for larger tables

    1: \ search order wordset                                 14may93py
    2: 
    3: $10 constant maxvp
    4: Variable vp
    5:   0 A, 0 A,  0 A, 0 A,   0 A, 0 A,   0 A, 0 A, 
    6:   0 A, 0 A,  0 A, 0 A,   0 A, 0 A,   0 A, 0 A, 
    7: 
    8: : get-current  ( -- wid )  current @ ;
    9: : set-current  ( wid -- )  current ! ;
   10: 
   11: : context ( -- addr )  vp dup @ cells + ;
   12: : definitions  ( -- )  context @ current ! ;
   13: 
   14: \ wordlist Vocabulary also previous                    14may93py
   15: 
   16: AVariable voclink
   17: 
   18: Defer 'initvoc
   19: ' drop IS 'initvoc
   20: 
   21: Variable slowvoc   slowvoc off
   22: 
   23: : wordlist  ( -- wid )
   24:   here  0 A, Forth-wordlist cell+ @ A, voclink @ A, slowvoc @ A,
   25:   dup 2 cells + dup voclink ! 'initvoc ;
   26: 
   27: : Vocabulary ( -- ) Create wordlist drop  DOES> context ! ;
   28: 
   29: : also  ( -- )
   30:   context @ vp @ 1+ dup maxvp > abort" Vocstack full"
   31:   vp ! context ! ;
   32: 
   33: : previous ( -- )  vp @ 1- dup 0= abort" Vocstack empty" vp ! ;
   34: 
   35: \ vocabulary find                                      14may93py
   36: 
   37: : (vocfind)  ( addr count nfa1 -- nfa2|false )
   38:     \ !! generalize this to be independent of vp
   39:     drop 1 vp @
   40:     DO  2dup vp I cells + @ (search-wordlist) dup
   41: 	IF  nip nip
   42: 	    UNLOOP EXIT
   43: 	THEN  drop
   44:     -1 +LOOP
   45:     2drop false ;
   46: 
   47: 0 value locals-wordlist
   48: 
   49: : (localsvocfind)  ( addr count nfa1 -- nfa2|false )
   50:     \ !! use generalized (vocfind)
   51:     drop locals-wordlist
   52:     IF 2dup locals-wordlist (search-wordlist) dup
   53: 	IF nip nip
   54: 	    EXIT
   55: 	THEN drop
   56:     THEN
   57:     0 (vocfind) ;
   58: 
   59: \ In the kernal the dictionary search works on only one wordlist.
   60: \ The following stuff builds a thing that looks to the kernal like one
   61: \ wordlist, but when searched it searches the whole search order
   62: \  (including locals)
   63: 
   64: \ this is the wordlist-map of the dictionary
   65: Create vocsearch       ' (localsvocfind) A, ' (reveal) A,  ' drop A,
   66: 
   67: \ Only root                                            14may93py
   68: 
   69: wordlist \ the wordlist structure
   70: vocsearch over cell+ A! \ patch the map into it
   71: 
   72: Vocabulary Forth
   73: Vocabulary Root
   74: 
   75: : Only  vp off  also Root also definitions ;
   76: 
   77: \ set initial search order                             14may93py
   78: 
   79: Forth-wordlist @ ' Forth >body A!
   80: 
   81: Only Forth also definitions
   82: 
   83: search A! \ our dictionary search order becomes the law
   84: 
   85: \ get-order set-order                                  14may93py
   86: 
   87: : get-order  ( -- wid1 .. widn n )
   88:   vp @ 0 ?DO  vp cell+ I cells + @  LOOP  vp @ ;
   89: 
   90: : set-order  ( wid1 .. widn n / -1 -- )
   91:   dup -1 = IF  drop Only exit  THEN  dup vp !
   92:   ?dup IF  1- FOR  vp cell+ I cells + !  NEXT  THEN ;
   93: 
   94: : seal ( -- )  context @ 1 set-order ;
   95: 
   96: \ words visible in roots                               14may93py
   97: 
   98: : .name ( name -- ) name>string type space ;
   99: : words  cr 0 context @
  100:   BEGIN  @ dup  WHILE  2dup cell+ c@ $1F and 2 + dup >r +
  101:          &79 >  IF  cr nip 0 swap  THEN
  102:          dup .name space r> rot + swap  REPEAT 2drop ;
  103: 
  104: : body> ( data -- cfa )  0 >body - ;
  105: 
  106: : .voc  body> >name .name ;
  107: : order  1 vp @  DO  vp I cells + @ .voc  -1 +LOOP  2 spaces
  108:   current @ .voc ;
  109: : vocs   voclink  BEGIN  @ dup @  WHILE  dup 2 cells - .voc  REPEAT  drop ;
  110: 
  111: Root definitions
  112: 
  113: ' words Alias words
  114: ' Forth Alias Forth
  115: 
  116: Forth definitions
  117: 
  118: include hash.fs

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