\ search order wordset 14may93py
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$10 constant maxvp
Variable vp
0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A,
0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A, 0 A,
: get-current ( -- wid ) current @ ;
: set-current ( wid -- ) current ! ;
\ : context ( -- addr ) vp dup @ cells + ;
: vp! dup vp ! cells vp + to context ;
: definitions ( -- ) context @ current ! ;
\ wordlist Vocabulary also previous 14may93py
Variable slowvoc 0 slowvoc !
\ Forth-wordlist AConstant Forth-wordlist
: mappedwordlist ( map-struct -- wid ) \ gforth
\G creates a wordlist with a special map-structure
here swap A, 0 A, voclink @ A, 0 A,
dup wordlist-link voclink !
dup initvoc ;
: wordlist ( -- wid )
slowvoc @
IF \ this is now f83search because hashing may be loaded already
\ jaw
f83search
ELSE Forth-wordlist wordlist-map @ THEN
mappedwordlist ;
: Vocabulary ( -- ) Create wordlist drop DOES> context ! ;
: also ( -- )
context @ vp @ 1+ dup maxvp > abort" Vocstack full"
vp! context ! ;
: previous ( -- ) vp @ 1- dup 0= abort" Vocstack empty" vp! ;
\ vocabulary find 14may93py
: (vocfind) ( addr count wid -- nfa|false )
\ !! generalize this to be independent of vp
drop vp dup @ 1- cells over +
DO 2dup I 2@ over <>
IF (search-wordlist) dup
IF nip nip UNLOOP EXIT
THEN drop
ELSE drop 2drop THEN
[ -1 cells ] Literal +LOOP
2drop false ;
0 value locals-wordlist
: (localsvocfind) ( addr count wid -- nfa|false )
\ !! use generalized (vocfind)
drop locals-wordlist
IF 2dup locals-wordlist (search-wordlist) dup
IF nip nip
EXIT
THEN drop
THEN
0 (vocfind) ;
\ In the kernel the dictionary search works on only one wordlist.
\ The following stuff builds a thing that looks to the kernel like one
\ wordlist, but when searched it searches the whole search order
\ (including locals)
\ this is the wordlist-map of the dictionary
Create vocsearch ( -- wordlist-map )
' (localsvocfind) A, ' (reveal) A, ' drop A, ' drop A,
\ create dummy wordlist for kernel
slowvoc on
vocsearch mappedwordlist \ the wordlist structure ( -- wid )
\ we don't want the dummy wordlist in our linked list
0 Voclink !
slowvoc off
\ Only root 14may93py
Vocabulary Forth
Vocabulary Root
: Only 1 vp! Root also ;
\ set initial search order 14may93py
Forth-wordlist wordlist-id @ ' Forth >body wordlist-id !
0 vp! also Root also definitions
Only Forth also definitions
lookup ! \ our dictionary search order becomes the law ( -- )
' Forth >body to Forth-wordlist \ "forth definitions get-current" and "forth-wordlist" should produce the same wid
\ get-order set-order 14may93py
: get-order ( -- wid1 .. widn n )
vp @ 0 ?DO vp cell+ I cells + @ LOOP vp @ ;
: set-order ( wid1 .. widn n / -1 -- )
dup -1 = IF drop Only exit THEN dup vp!
?dup IF 1- FOR vp cell+ I cells + ! NEXT THEN ;
: seal ( -- ) context @ 1 set-order ;
: .voc
body> >head name>string type space ;
: order ( -- ) \ search-ext
\g prints the search order and the @code{current} wordlist. The
\g standard requires that the wordlists are printed in the order
\g in which they are searched. Therefore, the output is reversed
\g with respect to the conventional way of displaying stacks. The
\g @code{current} wordlist is displayed last.
get-order 0
?DO
.voc
LOOP
4 spaces get-current .voc ;
: vocs ( -- ) \ gforth
\g prints vocabularies and wordlists defined in the system.
voclink
BEGIN
@ dup
WHILE
dup 0 wordlist-link - .voc
REPEAT
drop ;
Root definitions
' words Alias words
' Forth Alias Forth
' forth-wordlist alias forth-wordlist
' set-order alias set-order
' order alias order
Forth definitions
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