return NEXT
end)
-# Outer interpreter
-
-COMMA_CFA = defPrimWord(",", () -> begin
- mem[mem[H]] = popPS()
- mem[H] += 1
-
- return NEXT
-end)
-
-BTICK_CFA = defWord("[']",
- [FROMR_CFA, DUP_CFA, INCR_CFA, TOR_CFA, FETCH_CFA, EXIT_CFA])
-
-EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin
- reg.W = popPS()
- return mem[reg.W]
-end)
+# Interpreter/Compiler-specific I/O
TIB_CFA = defConst("TIB", TIB)
NUMTIB, NUMTIB_CFA = defNewVar("#TIB", 0)
return NEXT
end)
-PARSE_CFA = defPrimWord("PARSE", () -> begin
- delim = popPS()
-
- # Chew up initial occurrences of delim
- addr = mem[H]
-
- # Start reading input stream
- count = 0
- while (mem[TOIN]<mem[NUMTIB])
- mem[addr] = mem[TIB+mem[TOIN]]
- mem[TOIN] += 1
-
- if (mem[addr] == delim)
- break
- end
-
- count += 1
- addr += 1
- end
-
- pushPS(addr)
- pushPS(count)
-
- return NEXT
-end)
-
-BYE_CFA = defPrimWord("BYE", () -> begin
- println("\nBye!")
- return 0
-end)
+# Compilation
STATE, STATE_CFA = defNewVar("STATE", 0)
-INTERPRET_CFA = defWord("INTERPRET",
- [LIT_CFA, 32, WORD_CFA, # Read next space-delimited word
-
- DUP_CFA, FETCH_CFA, ZE_CFA, ZBRANCH_CFA, 3,
- DROP_CFA, EXIT_CFA, # Exit if TIB is exhausted
-
- STATE_CFA, FETCH_CFA, ZBRANCH_CFA, 24,
- # Compiling
- FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 13,
-
- # Found word.
- LIT_CFA, -1, EQ_CFA, INVERT_CFA, ZBRANCH_CFA, 4,
-
- # Immediate: Execute!
- EXECUTE_CFA, BRANCH_CFA, -26,
-
- # Not immediate: Compile!
- COMMA_CFA, BRANCH_CFA, -29,
-
- # No word found, parse number
- NUMBER_CFA, BTICK_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
-
- # Interpreting
- FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
-
- # Found word. Execute!
- DROP_CFA, EXECUTE_CFA, BRANCH_CFA, -44,
-
- # No word found, parse number and leave on stack
- NUMBER_CFA, BRANCH_CFA, -47,
- EXIT_CFA])
-
-PROMPT_CFA = defPrimWord("PROMPT", () -> begin
- if (mem[STATE] == 0 && currentSource() == STDIN)
- println(" ok")
- end
-
- return NEXT
-end)
-
-QUIT_CFA = defWord("QUIT",
- [LIT_CFA, 0, STATE_CFA, STORE_CFA,
- LIT_CFA, 0, NUMTIB_CFA, STORE_CFA,
- RSP0_CFA, RSPSTORE_CFA,
- QUERY_CFA,
- INTERPRET_CFA, PROMPT_CFA,
- BRANCH_CFA,-4])
-
-ABORT_CFA = defWord("ABORT",
- [PSP0_CFA, PSPSTORE_CFA, QUIT_CFA])
-
-INCLUDE_CFA = defPrimWord("INCLUDE", () -> begin
- pushPS(32)
- callPrim(mem[WORD_CFA])
- wordAddr = popPS()+1
- wordLen = mem[wordAddr-1]
- word = getString(wordAddr, wordLen)
-
- push!(sources, open(word, "r"))
-
- # Clear input buffer
- mem[NUMTIB] = 0
+COMMA_CFA = defPrimWord(",", () -> begin
+ mem[mem[H]] = popPS()
+ mem[H] += 1
return NEXT
end)
-# Compilation
+BTICK_CFA = defWord("[']",
+ [FROMR_CFA, DUP_CFA, INCR_CFA, TOR_CFA, FETCH_CFA, EXIT_CFA])
HERE_CFA = defWord("HERE",
[H_CFA, FETCH_CFA, EXIT_CFA])
return NEXT
end, flags=F_IMMED)
+# Outer Interpreter
+
+EXECUTE_CFA = defPrimWord("EXECUTE", () -> begin
+ reg.W = popPS()
+ return mem[reg.W]
+end)
+
+INTERPRET_CFA = defWord("INTERPRET",
+ [LIT_CFA, 32, WORD_CFA, # Read next space-delimited word
+
+ DUP_CFA, FETCH_CFA, ZE_CFA, ZBRANCH_CFA, 3,
+ DROP_CFA, EXIT_CFA, # Exit if TIB is exhausted
+
+ STATE_CFA, FETCH_CFA, ZBRANCH_CFA, 24,
+ # Compiling
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 13,
+
+ # Found word.
+ LIT_CFA, -1, EQ_CFA, INVERT_CFA, ZBRANCH_CFA, 4,
+
+ # Immediate: Execute!
+ EXECUTE_CFA, BRANCH_CFA, -26,
+
+ # Not immediate: Compile!
+ COMMA_CFA, BRANCH_CFA, -29,
+
+ # No word found, parse number
+ NUMBER_CFA, BTICK_CFA, LIT_CFA, COMMA_CFA, COMMA_CFA, BRANCH_CFA, -36,
+
+ # Interpreting
+ FIND_CFA, QDUP_CFA, ZBRANCH_CFA, 5,
+
+ # Found word. Execute!
+ DROP_CFA, EXECUTE_CFA, BRANCH_CFA, -44,
+
+ # No word found, parse number and leave on stack
+ NUMBER_CFA, BRANCH_CFA, -47,
+ EXIT_CFA])
+
+PROMPT_CFA = defPrimWord("PROMPT", () -> begin
+ if (mem[STATE] == 0 && currentSource() == STDIN)
+ println(" ok")
+ end
+
+ return NEXT
+end)
+
+QUIT_CFA = defWord("QUIT",
+ [LIT_CFA, 0, STATE_CFA, STORE_CFA,
+ LIT_CFA, 0, NUMTIB_CFA, STORE_CFA,
+ RSP0_CFA, RSPSTORE_CFA,
+ QUERY_CFA,
+ INTERPRET_CFA, PROMPT_CFA,
+ BRANCH_CFA,-4])
+
+ABORT_CFA = defWord("ABORT",
+ [PSP0_CFA, PSPSTORE_CFA, QUIT_CFA])
+
+BYE_CFA = defPrimWord("BYE", () -> begin
+ println("\nBye!")
+ return 0
+end)
+
+# File I/O
+
+INCLUDE_CFA = defPrimWord("INCLUDE", () -> begin
+ pushPS(32)
+ callPrim(mem[WORD_CFA])
+ wordAddr = popPS()+1
+ wordLen = mem[wordAddr-1]
+ word = getString(wordAddr, wordLen)
+
+ push!(sources, open(word, "r"))
+
+ # Clear input buffer
+ mem[NUMTIB] = 0
+
+ return NEXT
+end)
+
#### VM loop ####
#TIB @ >IN !
; \ We can now comment!
-\ BASIC DEFINITIONS ----------------------------------------------------------------------
-
-: / /MOD SWAP DROP ;
-: MOD /MOD DROP ;
-: */ -ROT * SWAP / ;
-
-: NEGATE 0 SWAP - ;
-
-: TRUE -1 ;
-: FALSE 0 ;
-: NOT 0= ;
-
-\ Translate a number of cells into memory units
-\ (in our case 1 cell = 1 memory unit)
-: CELLS ;
-
-\ Since the smallest unit of memory in our system is 64 bits and since strings
-\ are stored as arrays of 64 bit integers, the character store/fetch words are
-\ just aliases of the standard store/fetch words.
-: C! ! ;
-: C@ @ ;
-: C, , ;
-
-: DEPTH PSP@ PSP0 - ;
-
-: '\n' 10 ;
-: BL 32 ;
-
-: LITERAL IMMEDIATE ['] LIT , , ;
-
-: ' BL WORD FIND DROP ;
-
-: CHAR BL WORD 1+ @ ;
-: [CHAR] IMMEDIATE
- CHAR
- ['] LIT , ,
-;
-
-: CR '\n' emit ;
-: SPACE BL emit ;
-
-: [COMPILE] IMMEDIATE
- BL WORD \ get the next word
- FIND DROP \ find it in the dictionary
- , \ and compile that
-;
-
-: RECURSE IMMEDIATE
- LATEST @ \ LATEST points to the word being compiled at the moment
- >CFA \ get the codeword
- , \ compile it
-;
-
-\ CONTROL STRUCTURES ----------------------------------------------------------------------
-
-: IF IMMEDIATE
- ['] 0BRANCH , \ compile 0BRANCH
- HERE \ save location of the offset on the stack
- 0 , \ compile a dummy offset
-;
-
-: THEN IMMEDIATE
- DUP
- HERE SWAP - \ calculate the offset from the address saved on the stack
- SWAP ! \ store the offset in the back-filled location
-;
-
-: ELSE IMMEDIATE
- ['] BRANCH , \ definite branch to just over the false-part
- HERE \ save location of the offset on the stack
- 0 , \ compile a dummy offset
- SWAP \ now back-fill the original (IF) offset
- DUP \ same as for THEN word above
- HERE SWAP -
- SWAP !
-;
-
-: BEGIN IMMEDIATE
- HERE \ save location on the stack
-;
-
-: UNTIL IMMEDIATE
- ['] 0BRANCH , \ compile 0BRANCH
- HERE - \ calculate the offset from the address saved on the stack
- , \ compile the offset here
-;
-
-: AGAIN IMMEDIATE
- ['] BRANCH , \ compile BRANCH
- HERE - \ calculate the offset back
- , \ compile the offset here
-;
-
-: WHILE IMMEDIATE
- ['] 0BRANCH , \ compile 0BRANCH
- HERE \ save location of the offset2 on the stack
- 0 , \ compile a dummy offset2
-;
-
-: REPEAT IMMEDIATE
- ['] BRANCH , \ compile BRANCH
- SWAP \ get the original offset (from BEGIN)
- HERE - , \ and compile it after BRANCH
- DUP
- HERE SWAP - \ calculate the offset2
- SWAP ! \ and back-fill it in the original location
-;
-
-: UNLESS IMMEDIATE
- ['] NOT , \ compile NOT (to reverse the test)
- [COMPILE] IF \ continue by calling the normal IF
-;
-
-: DO IMMEDIATE
- ['] LIT , -1 , [COMPILE] IF
- ['] >R , ['] >R ,
- ['] LIT , HERE 0 , ['] >R ,
- HERE
-;
-
-: ?DO IMMEDIATE
- ['] 2DUP , ['] - , [COMPILE] IF
- ['] >R , ['] >R ,
- ['] LIT , HERE 0 , ['] >R ,
- HERE
-;
-
-: I RSP@ 3 - @ ;
-
-: J RSP@ 6 - @ ;
-
-: ?LEAVE IMMEDIATE
- ['] 0BRANCH , 13 ,
- ['] R> , ['] RDROP , ['] RDROP ,
- ['] LIT , HERE 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! ,
- ['] BRANCH ,
- 0 ,
-;
-
-: LEAVE IMMEDIATE
- ['] LIT , -1 ,
- [COMPILE] ?LEAVE
-;
-
-: +LOOP IMMEDIATE
-
- ['] DUP , \ Store copy of increment
-
- ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] + , ['] 2DUP , ['] - ,
- ['] SWAP , ['] >R , ['] SWAP , ['] >R , ['] SWAP , ['] >R ,
-
- \ Condition differently depending on sign of increment
- ['] SWAP , ['] 0>= , [COMPILE] IF
- ['] 0<= ,
- [COMPILE] ELSE
- ['] 0> ,
- [COMPILE] THEN
-
- \ Branch back to begining of loop kernel
- ['] 0BRANCH , HERE - ,
-
- \ Clean up
- ['] RDROP , ['] RDROP , ['] RDROP ,
-
- \ Record address of loop end for any LEAVEs to use
- HERE SWAP !
-
- [COMPILE] ELSE
- ['] 2DROP , \ Clean up if loop was entirely skipped (?DO)
- [COMPILE] THEN
-;
-
-: LOOP IMMEDIATE
- ['] LIT , 1 ,
- [COMPILE] +LOOP
-;
-
-
-\ CASE ------------------------------------------------------------------------
-
-: CASE IMMEDIATE
- 0 \ push 0 to mark the bottom of the stack
-;
-
-: OF IMMEDIATE
- ['] OVER , \ compile OVER
- ['] = , \ compile =
- [COMPILE] IF \ compile IF
- ['] DROP , \ compile DROP
-;
-
-: ENDOF IMMEDIATE
- [COMPILE] ELSE \ ENDOF is the same as ELSE
-;
-
-: ENDCASE IMMEDIATE
- ['] DROP , \ compile DROP
-
- \ keep compiling THEN until we get to our zero marker
- BEGIN
- ?DUP
- WHILE
- [COMPILE] THEN
- REPEAT
-;
-
-
-\ COMMENTS ----------------------------------------------------------------------
-
-: ( IMMEDIATE
- 1 \ allowed nested parens by keeping track of depth
- BEGIN
- >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
- ELSE
- [CHAR] ) = IF \ close paren?
- 1- \ depth decreases
- THEN
- THEN
- DUP 0= UNTIL \ continue until we reach matching close paren, depth 0
- DROP \ drop the depth counter
-;
-
-( Some more complicated stack examples, showing the stack notation. )
-: NIP ( x y -- y ) SWAP DROP ;
-: TUCK ( x y -- y x y ) DUP -ROT ;
-: PICK ( x_u ... x_1 x_0 u -- x_u ... x_1 x_0 x_u )
- 1+ ( add one because of 'u' on the stack )
- PSP@ SWAP - ( add to the stack pointer )
- @ ( and fetch )
-;
-: ROLL ( x_u x_u-1... x_0 u -- x_u-1 ... x_0 x_u )
- 1+ DUP PICK SWAP ( x_u x_u-1 ... x_0 x_u u+1 )
- PSP@ 1- SWAP - PSP@ 2- SWAP
- DO
- i 1+ @ i !
- LOOP
- SWAP DROP
-;
-
-( With the looping constructs, we can now write SPACES, which writes n spaces to stdout. )
-: SPACES ( n -- )
- DUP 0> IF
- 0 DO SPACE LOOP
- ELSE
- DROP
- THEN
-;
-
-( Standard words for manipulating BASE. )
-: DECIMAL ( -- ) 10 BASE ! ;
-: HEX ( -- ) 16 BASE ! ;
-
-( Compute absolute value. )
-: ABS ( n -- |n| )
- dup 0< if
- negate
- then
-;
-
-: MAX ( n m -- max )
- 2dup - 0< if
- swap drop
- else
- drop
- then
-;
-
-: MIN ( n m -- max )
- 2dup - 0> if
- swap drop
- else
- drop
- then
-;
-
-( PRINTING NUMBERS ---------------------------------------------------------------------- )
-
-( This is the underlying recursive definition of U. )
-: U. ( u -- )
- BASE @ /MOD ( width rem quot )
- ?DUP IF ( if quotient <> 0 then )
- RECURSE ( print the quotient )
- THEN
-
- ( print the remainder )
- DUP 10 < IF
- [CHAR] 0 ( decimal digits 0..9 )
- ELSE
- 10 - ( hex and beyond digits A..Z )
- [CHAR] A
- THEN
- +
- EMIT
-;
-
-( This word returns the width (in characters) of an unsigned number in the current base )
-: UWIDTH ( u -- width )
- BASE @ / ( rem quot )
- ?DUP IF ( if quotient <> 0 then )
- RECURSE 1+ ( return 1+recursive call )
- ELSE
- 1 ( return 1 )
- THEN
-;
-
-: U.R ( u width -- )
- SWAP ( width u )
- DUP ( width u u )
- UWIDTH ( width u uwidth )
- ROT ( u uwidth width )
- SWAP - ( u width-uwidth )
- ( At this point if the requested width is narrower, we'll have a negative number on the stack.
- Otherwise the number on the stack is the number of spaces to print. But SPACES won't print
- a negative number of spaces anyway, so it's now safe to call SPACES ... )
- SPACES
- ( ... and then call the underlying implementation of U. )
- U.
-;
-
-: .R ( n width -- )
- SWAP ( width n )
- DUP 0< IF
- NEGATE ( width u )
- 1 ( save a flag to remember that it was negative | width n 1 )
- -ROT ( 1 width u )
- SWAP ( 1 u width )
- 1- ( 1 u width-1 )
- ELSE
- 0 ( width u 0 )
- -ROT ( 0 width u )
- SWAP ( 0 u width )
- THEN
- SWAP ( flag width u )
- DUP ( flag width u u )
- UWIDTH ( flag width u uwidth )
- ROT ( flag u uwidth width )
- SWAP - ( flag u width-uwidth )
-
- SPACES ( flag u )
- SWAP ( u flag )
-
- IF ( was it negative? print the - character )
- [CHAR] - EMIT
- THEN
-
- U.
-;
-
-: . 0 .R SPACE ;
-
-: .S ( -- )
- [CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE
- PSP0 1+
- BEGIN
- DUP PSP@ 2 - <=
- WHILE
- DUP @ .
- 1+
- REPEAT
- DROP
-;
-
-: U. U. SPACE ;
-
-( ? fetches the integer at an address and prints it. )
-: ? ( addr -- ) @ . ;
-
-( c a b WITHIN returns true if a <= c and c < b )
-: WITHIN
- -ROT ( b c a )
- OVER ( b c a c )
- <= IF
- > IF ( b c -- )
- TRUE
- ELSE
- FALSE
- THEN
- ELSE
- 2DROP ( b c -- )
- FALSE
- THEN
-;
-
-
-( STRINGS ---------------------------------------------------------------------- )
-
-
-( Block copy, however, is important and novel: )
-: CMOVE ( src dest length -- )
-
- DUP 0<= IF
- EXIT
- THEN
-
- -ROT OVER - ( length src (dest-src) )
- -ROT DUP ROT + SWAP ( (dest-src) (src+length) src )
-
- DO
- I @ ( (dest-src) i@ )
- OVER I + ( (dest-src) i@ (dest-src+i) )
- ! ( (dest-src) )
- LOOP
-
- DROP
-;
-
-( C, appends a byte to the current compiled word. )
-: C,
- HERE C!
- 1 H +!
-;
-
-: S" IMMEDIATE ( -- addr len )
- STATE @ IF ( compiling? )
- ['] 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 )
-
- BEGIN
- >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 )
- REPEAT
- DROP ( drop the double quote character at the end )
- DUP ( get the saved address of the length word )
- HERE SWAP - ( calculate the length )
- 1- ( subtract 1 (because we measured from the start of the length word) )
- SWAP ! ( and back-fill the length location )
- ELSE ( immediate mode )
- HERE ( get the start address of the temporary space )
-
- BEGIN
- >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 )
- 1+ ( increment address )
- REPEAT
- DROP ( drop the final " character )
- HERE - ( calculate the length )
- HERE ( push the start address )
- SWAP ( addr len )
- THEN
-;
-
-: ." IMMEDIATE ( -- )
- [COMPILE] S" ( read the string, and compile LITSTRING, etc. )
- ['] TYPE , ( compile the final TYPE )
-;
-
-: .(
- BEGIN
- >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 )
- THEN
- EMIT
- 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
- CREATE ,
-DOES> @
-;
-
-: ALLOT ( n -- )
- H +! ( adds n to H, after this the old value of H is still on the stack )
-;
-
-: VARIABLE
- CREATE
- 1 CELLS ALLOT ( allocate 1 cell of memory, push the pointer to this memory )
-;
-
-: VALUE ( n -- )
- CREATE ,
-DOES> @
-;
-
-: TO IMMEDIATE ( n -- )
- BL WORD ( get the name of the value )
- FIND DROP ( look it up in the dictionary )
- >BODY ( get a pointer to the first data field (the 'LIT') )
- STATE @ IF ( compiling? )
- ['] LIT , ( compile LIT )
- , ( compile the address of the value )
- ['] ! , ( compile ! )
- ELSE ( immediate mode )
- ! ( update it straightaway )
- THEN
-;
-
-( x +TO VAL adds x to VAL )
-: +TO IMMEDIATE
- BL WORD ( get the name of the value )
- FIND DROP ( look it up in the dictionary )
- >BODY ( get a pointer to the first data field (the 'LIT') )
- STATE @ IF ( compiling? )
- ['] LIT , ( compile LIT )
- , ( compile the address of the value )
- ['] +! , ( compile +! )
- ELSE ( immediate mode )
- +! ( update it straightaway )
- THEN
-;
-
-( Fill u ints, starting at a, with the value b )
-: FILL ( a u b -- )
- -ROT OVER + SWAP ?DO
- DUP I !
- LOOP
- DROP
-;
-
-: ERASE ( a u -- )
- 0 FILL
-;
-
-( PRINTING THE DICTIONARY ------------------------------------------------------ )
-
-: .NAME
- DUP @ ( get the flags/length byte )
- F_LENMASK AND ( mask out the flags - just want the length )
-
- BEGIN
- DUP 0> ( length > 0? )
- WHILE
- SWAP 1+ ( addr len -- len addr+1 )
- DUP @ ( len addr -- len addr char | get the next character)
- DUP 32 >= OVER 127 <= AND IF
- EMIT ( len addr char -- len addr | and print it)
- ELSE
- BASE @ SWAP HEX
- ." \x" 0 .R
- BASE !
- THEN
- SWAP 1- ( len addr -- addr len-1 | subtract one from length )
- REPEAT
- 2DROP ( len addr -- )
-;
-
-: ?HIDDEN
- 1+ ( skip over the link pointer )
- @ ( get the flags/length byte )
- F_HIDDEN AND ( mask the F_HIDDEN flag and return it (as a truth value) )
-;
-: ?IMMEDIATE
- 1+ ( skip over the link pointer )
- @ ( get the flags/length byte )
- F_IMMED AND ( mask the F_IMMED flag and return it (as a truth value) )
-;
-
-: WORDS
- CR
- LATEST @ ( start at LATEST dictionary entry )
- BEGIN
- ?DUP ( while link pointer is not null )
- WHILE
- DUP ?HIDDEN NOT IF ( ignore hidden words )
- DUP 1+ .NAME ( but if not hidden, print the word )
- SPACE
- THEN
- @ ( dereference the link pointer - go to previous word )
- REPEAT
- CR
-;
-
-( DUMP ------------------------------------------------------------------------ )
-
-\ TODO!
-
-
-( DECOMPILER ------------------------------------------------------------------ )
-
-: >NAME
- BEGIN
- 1- DUP @
- NFA_MARK AND
- NFA_MARK = UNTIL
-;
-
-: >LFA >NAME 1- ;
-
-: SEE
- BL WORD FIND ( find the dictionary entry to decompile )
-
- CR
-
- 0= IF
- ." Word '" COUNT TYPE ." ' not found in dictionary."
- EXIT
- THEN
-
- >LFA
-
- ( 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). )
- HERE ( address of the end of the last compiled word )
- LATEST @ ( word last curr )
- BEGIN
- 2 PICK ( word last curr word )
- OVER ( word last curr word curr )
- <> ( word last curr word<>curr? )
- WHILE ( word last curr )
- NIP ( word curr )
- DUP @ ( word curr prev (which becomes: word last curr) )
- REPEAT
-
- DROP ( at this point, the stack is: start-of-word end-of-word )
- SWAP ( end-of-word start-of-word )
-
- DUP >CFA @ CASE
- DOCOL OF
- \ Colon definition
- [CHAR] : EMIT SPACE DUP 1+ .NAME SPACE
- DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR
- ENDOF
- DOVAR OF
- \ Variable definition
- ." Variable " DUP 1+ .NAME CR
- 2DROP EXIT
- ENDOF
- DOCON OF
- \ Constant definition
- ." Constant " DUP 1+ .NAME CR
- 2DROP EXIT
- ENDOF
-
- \ Unknown codeword
- ." Primitive or word with unrecognized codeword." CR
- DROP 2DROP EXIT
- ENDCASE
-
- 4 SPACES
-
- >CFA >BODY ( 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 )
- 2DUP >
- WHILE
- DUP @ ( end start codeword )
-
- CASE
- ['] LIT OF ( is it LIT ? )
- 1+ DUP @ ( get next word which is the integer constant )
- . ( and print it )
- ENDOF
- ['] LITSTRING OF ( is it LITSTRING ? )
- [CHAR] S EMIT [CHAR] " EMIT SPACE ( print S"<space> )
- 1+ DUP @ ( get the length word )
- SWAP 1+ SWAP ( end start+1 length )
- 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 )
- ENDOF
- ['] 0BRANCH OF ( is it 0BRANCH ? )
- ." 0BRANCH ( "
- 1+ DUP @ ( print the offset )
- .
- ." ) "
- ENDOF
- ['] BRANCH OF ( is it BRANCH ? )
- ." BRANCH ( "
- 1+ DUP @ ( print the offset )
- .
- ." ) "
- ENDOF
- ['] ['] OF ( is it ['] ? )
- ." ['] "
- 1+ DUP @ ( get the next codeword )
- >NAME ( and force it to be printed as a dictionary entry )
- .NAME SPACE
- ENDOF
- ['] EXIT OF ( is it EXIT? )
- ( We expect the last word to be EXIT, and if it is then we don't print it
- because EXIT is normally implied by ;. EXIT can also appear in the middle
- of words, and then it needs to be printed. )
- 2DUP ( end start end start )
- 1+ ( end start end start+1 )
- <> IF ( end start | we're not at the end )
- ." EXIT "
- THEN
- ENDOF
- ( default case: )
- DUP ( in the default case we always need to DUP before using )
- >NAME ( look up the codeword to get the dictionary entry )
- .NAME SPACE ( and print it )
- ENDCASE
-
- 1+ ( end start+1 )
- REPEAT
-
- [CHAR] ; EMIT CR
-
- 2DROP ( restore stack )
-;
-
-
-( FORGET and HIDE ------------------------------------------------------------ )
-
-: FORGET
- BL WORD FIND >LFA ( find the word, gets the dictionary entry address )
- DUP @ LATEST ! ( set LATEST to point to the previous word )
- H ! ( and store H with the dictionary address )
-;
-
-: HIDE
- BL WORD FIND DROP >NAME
- DUP @ F_HIDDEN OR SWAP !
-;
-
-( MEMORY ------------------------------------------------------------------ )
-
-: UNUSED ( -- cells )
- MEMSIZE HERE - ;
+include lib_1_basic.4th
+include lib_2_control.4th
+include lib_3_comments.4th
+include lib_4_printnum.4th
+include lib_5_strings.4th
+include lib_6_variables.4th
+include lib_7_printwords.4th
+include lib_8_decompiler.4th
+
+include lib_9_misc.4th
--- /dev/null
+\ Basic definitions
+
+: / /MOD SWAP DROP ;
+: MOD /MOD DROP ;
+: */ -ROT * SWAP / ;
+
+: NEGATE \ ( x -- -x )
+ 0 SWAP - ;
+
+: NIP \ ( x y -- y )
+ SWAP DROP ;
+
+: TUCK \ ( x y -- y x y )
+ DUP -ROT ;
+
+: PICK \ ( x_u ... x_1 x_0 u -- x_u ... x_1 x_0 x_u )
+ 1+ PSP@ SWAP - @ ;
+
+: TRUE -1 ;
+: FALSE 0 ;
+: NOT 0= ;
+
+\ Standard words for manipulating BASE.
+: DECIMAL 10 BASE ! ;
+: HEX 16 BASE ! ;
+
+
+\ Translate a number of cells into memory units
+\ (in our case 1 cell = 1 memory unit)
+: CELLS ;
+
+\ Since the smallest unit of memory in our system is 64 bits and since strings
+\ are stored as arrays of 64 bit integers, the character store/fetch words are
+\ just aliases of the standard store/fetch words.
+: C! ! ;
+: C@ @ ;
+: C, , ;
+
+: DEPTH PSP@ PSP0 - ;
+
+: '\n' 10 ;
+: BL 32 ;
+
+: LITERAL IMMEDIATE ['] LIT , , ;
+
+: ' BL WORD FIND DROP ;
+
+: CHAR BL WORD 1+ @ ;
+: [CHAR] IMMEDIATE
+ CHAR
+ ['] LIT , ,
+;
+
+: CR '\n' emit ;
+: SPACE BL emit ;
+
+: [COMPILE] IMMEDIATE
+ BL WORD \ get the next word
+ FIND DROP \ find it in the dictionary
+ , \ and compile that
+;
+
+: RECURSE IMMEDIATE
+ LATEST @ \ LATEST points to the word being compiled at the moment
+ >CFA \ get the codeword
+ , \ compile it
+;
+
--- /dev/null
+\ Flow control
+
+: IF IMMEDIATE
+ ['] 0BRANCH , \ compile 0BRANCH
+ HERE \ save location of the offset on the stack
+ 0 , \ compile a dummy offset
+;
+
+: THEN IMMEDIATE
+ DUP
+ HERE SWAP - \ calculate the offset from the address saved on the stack
+ SWAP ! \ store the offset in the back-filled location
+;
+
+: ELSE IMMEDIATE
+ ['] BRANCH , \ definite branch to just over the false-part
+ HERE \ save location of the offset on the stack
+ 0 , \ compile a dummy offset
+ SWAP \ now back-fill the original (IF) offset
+ DUP \ same as for THEN word above
+ HERE SWAP -
+ SWAP !
+;
+
+: BEGIN IMMEDIATE
+ HERE \ save location on the stack
+;
+
+: UNTIL IMMEDIATE
+ ['] 0BRANCH , \ compile 0BRANCH
+ HERE - \ calculate the offset from the address saved on the stack
+ , \ compile the offset here
+;
+
+: AGAIN IMMEDIATE
+ ['] BRANCH , \ compile BRANCH
+ HERE - \ calculate the offset back
+ , \ compile the offset here
+;
+
+: WHILE IMMEDIATE
+ ['] 0BRANCH , \ compile 0BRANCH
+ HERE \ save location of the offset2 on the stack
+ 0 , \ compile a dummy offset2
+;
+
+: REPEAT IMMEDIATE
+ ['] BRANCH , \ compile BRANCH
+ SWAP \ get the original offset (from BEGIN)
+ HERE - , \ and compile it after BRANCH
+ DUP
+ HERE SWAP - \ calculate the offset2
+ SWAP ! \ and back-fill it in the original location
+;
+
+: UNLESS IMMEDIATE
+ ['] NOT , \ compile NOT (to reverse the test)
+ [COMPILE] IF \ continue by calling the normal IF
+;
+
+: DO IMMEDIATE
+ ['] LIT , -1 , [COMPILE] IF
+ ['] >R , ['] >R ,
+ ['] LIT , HERE 0 , ['] >R ,
+ HERE
+;
+
+: ?DO IMMEDIATE
+ ['] 2DUP , ['] - , [COMPILE] IF
+ ['] >R , ['] >R ,
+ ['] LIT , HERE 0 , ['] >R ,
+ HERE
+;
+
+: I RSP@ 3 - @ ;
+
+: J RSP@ 6 - @ ;
+
+: ?LEAVE IMMEDIATE
+ ['] 0BRANCH , 13 ,
+ ['] R> , ['] RDROP , ['] RDROP ,
+ ['] LIT , HERE 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! ,
+ ['] BRANCH ,
+ 0 ,
+;
+
+: LEAVE IMMEDIATE
+ ['] LIT , -1 ,
+ [COMPILE] ?LEAVE
+;
+
+: +LOOP IMMEDIATE
+
+ ['] DUP , \ Store copy of increment
+
+ ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] + , ['] 2DUP , ['] - ,
+ ['] SWAP , ['] >R , ['] SWAP , ['] >R , ['] SWAP , ['] >R ,
+
+ \ Condition differently depending on sign of increment
+ ['] SWAP , ['] 0>= , [COMPILE] IF
+ ['] 0<= ,
+ [COMPILE] ELSE
+ ['] 0> ,
+ [COMPILE] THEN
+
+ \ Branch back to begining of loop kernel
+ ['] 0BRANCH , HERE - ,
+
+ \ Clean up
+ ['] RDROP , ['] RDROP , ['] RDROP ,
+
+ \ Record address of loop end for any LEAVEs to use
+ HERE SWAP !
+
+ [COMPILE] ELSE
+ ['] 2DROP , \ Clean up if loop was entirely skipped (?DO)
+ [COMPILE] THEN
+;
+
+: LOOP IMMEDIATE
+ ['] LIT , 1 ,
+ [COMPILE] +LOOP
+;
+
+
+\ CASE ------------------------------------------------------------------------
+
+: CASE IMMEDIATE
+ 0 \ push 0 to mark the bottom of the stack
+;
+
+: OF IMMEDIATE
+ ['] OVER , \ compile OVER
+ ['] = , \ compile =
+ [COMPILE] IF \ compile IF
+ ['] DROP , \ compile DROP
+;
+
+: ENDOF IMMEDIATE
+ [COMPILE] ELSE \ ENDOF is the same as ELSE
+;
+
+: ENDCASE IMMEDIATE
+ ['] DROP , \ compile DROP
+
+ \ keep compiling THEN until we get to our zero marker
+ BEGIN
+ ?DUP
+ WHILE
+ [COMPILE] THEN
+ REPEAT
+;
--- /dev/null
+\ Parenthetic comments
+
+: ( IMMEDIATE
+ 1 \ allowed nested parens by keeping track of depth
+ BEGIN
+ >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
+ ELSE
+ [CHAR] ) = IF \ close paren?
+ 1- \ depth decreases
+ THEN
+ THEN
+ DUP 0= UNTIL \ continue until we reach matching close paren, depth 0
+ DROP \ drop the depth counter
+;
+
--- /dev/null
+\ Displaying numbers
+
+( Write n spaces to stdout. )
+: SPACES ( n -- )
+ DUP 0> IF
+ 0 DO SPACE LOOP
+ ELSE
+ DROP
+ THEN
+;
+( This is the underlying recursive definition of U. )
+: U. ( u -- )
+ BASE @ /MOD ( width rem quot )
+ ?DUP IF ( if quotient <> 0 then )
+ RECURSE ( print the quotient )
+ THEN
+
+ ( print the remainder )
+ DUP 10 < IF
+ [CHAR] 0 ( decimal digits 0..9 )
+ ELSE
+ 10 - ( hex and beyond digits A..Z )
+ [CHAR] A
+ THEN
+ +
+ EMIT
+;
+
+( This word returns the width (in characters) of an unsigned number in the current base )
+: UWIDTH ( u -- width )
+ BASE @ / ( rem quot )
+ ?DUP IF ( if quotient <> 0 then )
+ RECURSE 1+ ( return 1+recursive call )
+ ELSE
+ 1 ( return 1 )
+ THEN
+;
+
+: U.R ( u width -- )
+ SWAP ( width u )
+ DUP ( width u u )
+ UWIDTH ( width u uwidth )
+ ROT ( u uwidth width )
+ SWAP - ( u width-uwidth )
+ ( At this point if the requested width is narrower, we'll have a negative number on the stack.
+ Otherwise the number on the stack is the number of spaces to print. But SPACES won't print
+ a negative number of spaces anyway, so it's now safe to call SPACES ... )
+ SPACES
+ ( ... and then call the underlying implementation of U. )
+ U.
+;
+
+: .R ( n width -- )
+ SWAP ( width n )
+ DUP 0< IF
+ NEGATE ( width u )
+ 1 ( save a flag to remember that it was negative | width n 1 )
+ -ROT ( 1 width u )
+ SWAP ( 1 u width )
+ 1- ( 1 u width-1 )
+ ELSE
+ 0 ( width u 0 )
+ -ROT ( 0 width u )
+ SWAP ( 0 u width )
+ THEN
+ SWAP ( flag width u )
+ DUP ( flag width u u )
+ UWIDTH ( flag width u uwidth )
+ ROT ( flag u uwidth width )
+ SWAP - ( flag u width-uwidth )
+
+ SPACES ( flag u )
+ SWAP ( u flag )
+
+ IF ( was it negative? print the - character )
+ [CHAR] - EMIT
+ THEN
+
+ U.
+;
+
+: . 0 .R SPACE ;
+
+: .S ( -- )
+ [CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE
+ PSP0 1+
+ BEGIN
+ DUP PSP@ 2 - <=
+ WHILE
+ DUP @ .
+ 1+
+ REPEAT
+ DROP
+;
+
+: U. U. SPACE ;
+
+( ? fetches the integer at an address and prints it. )
+: ? ( addr -- ) @ . ;
+
+( c a b WITHIN returns true if a <= c and c < b )
+: WITHIN
+ -ROT ( b c a )
+ OVER ( b c a c )
+ <= IF
+ > IF ( b c -- )
+ TRUE
+ ELSE
+ FALSE
+ THEN
+ ELSE
+ 2DROP ( b c -- )
+ FALSE
+ THEN
+;
+
--- /dev/null
+\ Strings
+
+: CMOVE ( src dest length -- )
+
+ DUP 0<= IF
+ EXIT
+ THEN
+
+ -ROT OVER - ( length src (dest-src) )
+ -ROT DUP ROT + SWAP ( (dest-src) (src+length) src )
+
+ DO
+ I @ ( (dest-src) i@ )
+ OVER I + ( (dest-src) i@ (dest-src+i) )
+ ! ( (dest-src) )
+ LOOP
+
+ DROP
+;
+
+: S" IMMEDIATE ( -- addr len )
+ STATE @ IF ( compiling? )
+ ['] 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 )
+
+ BEGIN
+ >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 )
+ REPEAT
+ DROP ( drop the double quote character at the end )
+ DUP ( get the saved address of the length word )
+ HERE SWAP - ( calculate the length )
+ 1- ( subtract 1 (because we measured from the start of the length word) )
+ SWAP ! ( and back-fill the length location )
+ ELSE ( immediate mode )
+ HERE ( get the start address of the temporary space )
+
+ BEGIN
+ >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 )
+ 1+ ( increment address )
+ REPEAT
+ DROP ( drop the final " character )
+ HERE - ( calculate the length )
+ HERE ( push the start address )
+ SWAP ( addr len )
+ THEN
+;
+
+: ." IMMEDIATE ( -- )
+ [COMPILE] S" ( read the string, and compile LITSTRING, etc. )
+ ['] TYPE , ( compile the final TYPE )
+;
+
+: .(
+ BEGIN
+ >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 )
+ THEN
+ EMIT
+ AGAIN
+;
+
+( Converts address of counted string into address of
+ start of string and length of string. )
+: COUNT ( addr1 -- addr2 n )
+ DUP 1+ SWAP @ ;
+
+
--- /dev/null
+\ Constants and Variables
+
+: CONSTANT
+ CREATE ,
+DOES> @
+;
+
+: ALLOT ( n -- )
+ H +! ( adds n to H, after this the old value of H is still on the stack )
+;
+
+: VARIABLE
+ CREATE
+ 1 CELLS ALLOT ( allocate 1 cell of memory, push the pointer to this memory )
+;
+
+: VALUE ( n -- )
+ CREATE ,
+DOES> @
+;
+
+: TO IMMEDIATE ( n -- )
+ BL WORD ( get the name of the value )
+ FIND DROP ( look it up in the dictionary )
+ >BODY ( get a pointer to the first data field (the 'LIT') )
+ STATE @ IF ( compiling? )
+ ['] LIT , ( compile LIT )
+ , ( compile the address of the value )
+ ['] ! , ( compile ! )
+ ELSE ( immediate mode )
+ ! ( update it straightaway )
+ THEN
+;
+
+( x +TO VAL adds x to VAL )
+: +TO IMMEDIATE
+ BL WORD ( get the name of the value )
+ FIND DROP ( look it up in the dictionary )
+ >BODY ( get a pointer to the first data field (the 'LIT') )
+ STATE @ IF ( compiling? )
+ ['] LIT , ( compile LIT )
+ , ( compile the address of the value )
+ ['] +! , ( compile +! )
+ ELSE ( immediate mode )
+ +! ( update it straightaway )
+ THEN
+;
+
+( Fill u ints, starting at a, with the value b )
+: FILL ( a u b -- )
+ -ROT OVER + SWAP ?DO
+ DUP I !
+ LOOP
+ DROP
+;
+
+: ERASE ( a u -- )
+ 0 FILL
+;
--- /dev/null
+\ Display dictionary contents
+
+: .NAME
+ DUP @ ( get the flags/length byte )
+ F_LENMASK AND ( mask out the flags - just want the length )
+
+ BEGIN
+ DUP 0> ( length > 0? )
+ WHILE
+ SWAP 1+ ( addr len -- len addr+1 )
+ DUP @ ( len addr -- len addr char | get the next character)
+ DUP 32 >= OVER 127 <= AND IF
+ EMIT ( len addr char -- len addr | and print it)
+ ELSE
+ BASE @ SWAP HEX
+ ." \x" 0 .R
+ BASE !
+ THEN
+ SWAP 1- ( len addr -- addr len-1 | subtract one from length )
+ REPEAT
+ 2DROP ( len addr -- )
+;
+
+: ?HIDDEN
+ 1+ ( skip over the link pointer )
+ @ ( get the flags/length byte )
+ F_HIDDEN AND ( mask the F_HIDDEN flag and return it (as a truth value) )
+;
+: ?IMMEDIATE
+ 1+ ( skip over the link pointer )
+ @ ( get the flags/length byte )
+ F_IMMED AND ( mask the F_IMMED flag and return it (as a truth value) )
+;
+
+: WORDS
+ CR
+ LATEST @ ( start at LATEST dictionary entry )
+ BEGIN
+ ?DUP ( while link pointer is not null )
+ WHILE
+ DUP ?HIDDEN NOT IF ( ignore hidden words )
+ DUP 1+ .NAME ( but if not hidden, print the word )
+ SPACE
+ THEN
+ @ ( dereference the link pointer - go to previous word )
+ REPEAT
+ CR
+;
--- /dev/null
+\ Decompilation
+
+: >NAME
+ BEGIN
+ 1- DUP @
+ NFA_MARK AND
+ NFA_MARK = UNTIL
+;
+
+: >LFA >NAME 1- ;
+
+: SEE
+ BL WORD FIND ( find the dictionary entry to decompile )
+
+ CR
+
+ 0= IF
+ ." Word '" COUNT TYPE ." ' not found in dictionary."
+ EXIT
+ THEN
+
+ >LFA
+
+ ( 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). )
+ HERE ( address of the end of the last compiled word )
+ LATEST @ ( word last curr )
+ BEGIN
+ 2 PICK ( word last curr word )
+ OVER ( word last curr word curr )
+ <> ( word last curr word<>curr? )
+ WHILE ( word last curr )
+ NIP ( word curr )
+ DUP @ ( word curr prev (which becomes: word last curr) )
+ REPEAT
+
+ DROP ( at this point, the stack is: start-of-word end-of-word )
+ SWAP ( end-of-word start-of-word )
+
+ DUP >CFA @ CASE
+ DOCOL OF
+ \ Colon definition
+ [CHAR] : EMIT SPACE DUP 1+ .NAME SPACE
+ DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR
+ ENDOF
+ DOVAR OF
+ \ Variable definition
+ ." Variable " DUP 1+ .NAME CR
+ 2DROP EXIT
+ ENDOF
+ DOCON OF
+ \ Constant definition
+ ." Constant " DUP 1+ .NAME CR
+ 2DROP EXIT
+ ENDOF
+
+ \ Unknown codeword
+ ." Primitive or word with unrecognized codeword." CR
+ DROP 2DROP EXIT
+ ENDCASE
+
+ 4 SPACES
+
+ >CFA >BODY ( 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 )
+ 2DUP >
+ WHILE
+ DUP @ ( end start codeword )
+
+ CASE
+ ['] LIT OF ( is it LIT ? )
+ 1+ DUP @ ( get next word which is the integer constant )
+ . ( and print it )
+ ENDOF
+ ['] LITSTRING OF ( is it LITSTRING ? )
+ [CHAR] S EMIT [CHAR] " EMIT SPACE ( print S"<space> )
+ 1+ DUP @ ( get the length word )
+ SWAP 1+ SWAP ( end start+1 length )
+ 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 )
+ ENDOF
+ ['] 0BRANCH OF ( is it 0BRANCH ? )
+ ." 0BRANCH ( "
+ 1+ DUP @ ( print the offset )
+ .
+ ." ) "
+ ENDOF
+ ['] BRANCH OF ( is it BRANCH ? )
+ ." BRANCH ( "
+ 1+ DUP @ ( print the offset )
+ .
+ ." ) "
+ ENDOF
+ ['] ['] OF ( is it ['] ? )
+ ." ['] "
+ 1+ DUP @ ( get the next codeword )
+ >NAME ( and force it to be printed as a dictionary entry )
+ .NAME SPACE
+ ENDOF
+ ['] EXIT OF ( is it EXIT? )
+ ( We expect the last word to be EXIT, and if it is then we don't print it
+ because EXIT is normally implied by ;. EXIT can also appear in the middle
+ of words, and then it needs to be printed. )
+ 2DUP ( end start end start )
+ 1+ ( end start end start+1 )
+ <> IF ( end start | we're not at the end )
+ ." EXIT "
+ THEN
+ ENDOF
+ ( default case: )
+ DUP ( in the default case we always need to DUP before using )
+ >NAME ( look up the codeword to get the dictionary entry )
+ .NAME SPACE ( and print it )
+ ENDCASE
+
+ 1+ ( end start+1 )
+ REPEAT
+
+ [CHAR] ; EMIT CR
+
+ 2DROP ( restore stack )
+;
+
--- /dev/null
+\ Miscellaneous core words
+
+: ROLL ( x_u x_u-1... x_0 u -- x_u-1 ... x_0 x_u )
+ 1+ DUP PICK SWAP ( x_u x_u-1 ... x_0 x_u u+1 )
+ PSP@ 1- SWAP - PSP@ 2- SWAP
+ DO
+ i 1+ @ i !
+ LOOP
+ SWAP DROP
+;
+
+( Compute absolute value. )
+: ABS ( n -- |n| )
+ dup 0< if
+ negate
+ then
+;
+
+: MAX ( n m -- max )
+ 2dup - 0< if
+ swap drop
+ else
+ drop
+ then
+;
+
+: MIN ( n m -- max )
+ 2dup - 0> if
+ swap drop
+ else
+ drop
+ then
+;
+
+: FORGET
+ BL WORD FIND >LFA ( find the word, gets the dictionary entry address )
+ DUP @ LATEST ! ( set LATEST to point to the previous word )
+ H ! ( and store H with the dictionary address )
+;
+
+: HIDE
+ BL WORD FIND DROP >NAME
+ DUP @ F_HIDDEN OR SWAP !
+;
+
+: UNUSED ( -- cells )
+ MEMSIZE HERE - ;
The Lambda Lab / projects / forth.jl.git / commitdiff