: \ IMMEDIATE
- KEY
- 10 = 0BRANCH [ -5 , ]
+ #TIB @ >IN !
; \ We can now comment!
\ BASIC DEFINITIONS ----------------------------------------------------------------------
: C@ @ ;
: C, , ;
-: DEPTH PSP@ PSP0 @ - ;
+: DEPTH PSP@ PSP0 - ;
: '\n' 10 ;
: BL 32 ;
: LITERAL IMMEDIATE ['] LIT , , ;
+: ' BL WORD FIND >CFA ;
+
+: CHAR BL WORD 1+ @ ;
: [CHAR] IMMEDIATE
CHAR
['] LIT , ,
: SPACE BL emit ;
: [COMPILE] IMMEDIATE
- WORD \ get the next word
+ BL WORD \ get the next word
FIND \ find it in the dictionary
>CFA \ get its codeword
, \ and compile that
, \ compile it
;
-: DEBUGON TRUE DEBUG ! ;
-: DEBUGOFF FALSE DEBUG ! ;
-
\ CONTROL STRUCTURES ----------------------------------------------------------------------
: IF IMMEDIATE
;
: +LOOP IMMEDIATE
+
['] DUP , \ Store copy of increment
['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] + , ['] 2DUP , ['] - ,
: ( IMMEDIATE
1 \ allowed nested parens by keeping track of depth
BEGIN
- KEY \ read next character
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +!
DUP [CHAR] ( = IF \ open paren?
DROP \ drop the open paren
1+ \ depth increases
: .S ( -- )
[CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE
- PSP0 @ 1+
+ PSP0 1+
BEGIN
DUP PSP@ 2 - <=
WHILE
['] LITSTRING , ( compile LITSTRING )
HERE @ ( save the address of the length word on the stack )
0 , ( dummy length - we don't know what it is yet )
- KEY DROP
+
BEGIN
- KEY ( get next character of the string )
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
DUP [CHAR] " <>
WHILE
C, ( copy character )
SWAP ! ( and back-fill the length location )
ELSE ( immediate mode )
HERE @ ( get the start address of the temporary space )
- KEY DROP
+
BEGIN
- KEY
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
DUP [CHAR] " <>
WHILE
OVER C! ( save next character )
: ." IMMEDIATE ( -- )
[COMPILE] S" ( read the string, and compile LITSTRING, etc. )
- ['] TELL , ( compile the final TELL )
+ ['] TYPE , ( compile the final TYPE )
;
: .(
- KEY DROP
BEGIN
- KEY
+ >IN @ #TIB @ >= IF \ End of TIB?
+ QUERY \ Get next line
+ THEN
+
+ TIB >IN @ + @ 1 >IN +! \ Get char from TIB
+
DUP [CHAR] ) = IF
DROP ( drop the double quote character )
EXIT ( return from this function )
AGAIN
;
+( Converts address of counted string into address of
+ start of string and length of string. )
+: COUNT ( addr1 -- addr2 n )
+ DUP 1+ SWAP @ ;
+
( CONSTANTS AND VARIABLES ------------------------------------------------------ )
: CONSTANT
- WORD HEADER ( make dictionary entry (the name follows CONSTANT) )
+ BL WORD HEADER ( make dictionary entry (the name follows CONSTANT) )
DOCOL , ( append DOCOL (the codeword field of this word) )
['] LIT , ( append the codeword LIT )
, ( append the value on the top of the stack )
;
: VARIABLE
- CREATE
+ BL WORD HEADER
+ DOVAR ,
1 CELLS ALLOT ( allocate 1 cell of memory, push the pointer to this memory )
;
-
: VALUE ( n -- )
- WORD HEADER ( make the dictionary entry (the name follows VALUE) )
+ BL WORD HEADER ( make the dictionary entry (the name follows VALUE) )
DOCOL , ( append DOCOL )
['] LIT , ( append the codeword LIT )
, ( append the initial value )
;
: TO IMMEDIATE ( n -- )
- WORD ( get the name of the value )
+ BL WORD ( get the name of the value )
FIND ( look it up in the dictionary )
- >DFA ( get a pointer to the first data field (the 'LIT') )
+ >PFA ( get a pointer to the first data field (the 'LIT') )
1+ ( increment to point at the value )
STATE @ IF ( compiling? )
['] LIT , ( compile LIT )
( x +TO VAL adds x to VAL )
: +TO IMMEDIATE
- WORD ( get the name of the value )
+ BL WORD ( get the name of the value )
FIND ( look it up in the dictionary )
- >DFA ( get a pointer to the first data field (the 'LIT') )
+ >PFA ( get a pointer to the first data field (the 'LIT') )
1+ ( increment to point at the value )
STATE @ IF ( compiling? )
['] LIT , ( compile LIT )
( FORGET ---------------------------------------------------------------------- )
: FORGET
- WORD FIND ( find the word, gets the dictionary entry address )
+ BL WORD FIND ( find the word, gets the dictionary entry address )
DUP @ LATEST ! ( set LATEST to point to the previous word )
HERE ! ( and store HERE with the dictionary address )
;
;
: SEE
- WORD FIND ( find the dictionary entry to decompile )
+ BL WORD DUP FIND ( find the dictionary entry to decompile )
+
+ ?DUP 0= IF
+ ." Word '" COUNT TYPE ." ' not found in dictionary."
+ EXIT
+ THEN
+
+ SWAP DROP
( Now we search again, looking for the next word in the dictionary. This gives us
the length of the word that we will be decompiling. (Well, mostly it does). )
4 SPACES
- >DFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data )
+ >PFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data )
( now we start decompiling until we hit the end of the word )
BEGIN ( end start )
[CHAR] S EMIT [CHAR] " EMIT SPACE ( print S"<space> )
1+ DUP @ ( get the length word )
SWAP 1+ SWAP ( end start+1 length )
- 2DUP TELL ( print the string )
+ 2DUP TYPE ( print the string )
[CHAR] " EMIT SPACE ( finish the string with a final quote )
+ ( end start+1+len, aligned )
1- ( because we're about to add 4 below )
The Lambda Lab / projects / forth.jl.git / blobdiff