defer eval
defer print
+defer collect-garbage
+
\ ------ Types ------
variable nexttype
make-type symbol-type
make-type primitive-proc-type
make-type compound-proc-type
+make-type fileport-type
: istype? ( obj type -- obj bool )
over = ;
-\ ------ Cons cell memory ------ {{{
+\ ------ List-structured memory ------ {{{
+
+10000 constant scheme-memsize
-1000 constant scheme-memsize
create car-cells scheme-memsize allot
create car-type-cells scheme-memsize allot
create cdr-cells scheme-memsize allot
: inc-nextfree
nextfrees nextfree @ + @
+ nextfree !
- dup scheme-memsize < if
- nextfree !
- else
- bold fg red
+ nextfree @ scheme-memsize >= if
+ collect-garbage
+ then
+
+ nextfree @ scheme-memsize >= if
+ fg red bold
." Out of memory! Aborting."
reset-term abort
then
\ }}}
-\ ---- Garbage Collection ---- {{{
-
-variable gc-enabled
-false gc-enabled !
-
-: enable-gc
- true gc-enabled ! ;
+\ ---- Port I/O ---- {{{
-: disable-gc
- false gc-enabled ! ;
+: fileport>fid ( fileport -- fid )
+ drop ;
-: gc-enabled?
- gc-enabled @ ;
+: fid>fileport ( fid -- fileport )
+ fileport-type ;
-: pairlike? ( obj -- obj bool )
- pair-type istype? if true exit then
- string-type istype? if true exit then
- symbol-type istype? if true exit then
- compound-proc-type istype? if true exit then
-
- false
+: open-input-file ( addr n -- fileport )
+ r/o open-file drop fid>fileport
;
-: pairlike-marked? ( obj -- obj bool )
- over nextfrees + @ 0=
+: close-port ( fileport -- )
+ fileport>fid close-file drop
;
-: mark-pairlike ( obj -- obj )
- over nextfrees + 0 swap !
-;
+objvar console-i/o-port
+0 fileport-type console-i/o-port obj!
-: gc-unmark ( -- )
- scheme-memsize 0 do
- 1 nextfrees i + !
- loop
-;
+objvar current-input-port
+console-i/o-port obj@ current-input-port obj!
-defer gc-mark-trace
-: gc-mark-obj ( obj -- )
+: read-port ( fileport -- obj )
+ current-input-port obj!
+ read ;
- gc-mark-trace
-
- pairlike? invert if 2drop exit then
- pairlike-marked? if 2drop exit then
-
- mark-pairlike
-
- drop pair-type 2dup
-
- car recurse
- cdr recurse
-;
-
-: gc-sweep
- scheme-memsize nextfree !
- 0 scheme-memsize 1- do
- nextfrees i + @ 0<> if
- nextfree @ nextfrees i + !
- i nextfree !
- then
- -1 +loop
-;
+: read-console ( -- obj )
+ console-i/o-port obj@ read-port ;
\ }}}
;
-: (create-symbol) ( addr n -- symbol-obj )
+: cstr>charlist ( addr n -- symbol-obj )
dup 0= if
2drop nil
else
bl word
count
- (create-symbol)
+ cstr>charlist
drop symbol-type
2dup
\ }}}
-\ ---- Primitives ---- {{{
-
-: make-primitive ( cfa -- )
- bl word
- count
-
- \ 2dup ." Defining primitive " type ." ..." cr
-
- (create-symbol)
- drop symbol-type
-
- 2dup
-
- symbol-table obj@
- cons
- symbol-table obj!
-
- rot primitive-proc-type ( var prim )
- global-env obj@ define-var
-;
-
-: arg-count-error
- bold fg red ." Incorrect argument count." reset-term cr
- abort
-;
-
-: ensure-arg-count ( args n -- )
- dup 0= if
- drop nil objeq? false = if
- arg-count-error
- then
- else
- -rot 2dup nil objeq? if
- arg-count-error
- then
-
- cdr rot 1- recurse
- then
-;
-
-: arg-type-error
- bold fg red ." Incorrect argument type." reset-term cr
- abort
-;
-
-: ensure-arg-type ( arg type -- arg )
- istype? false = if
- arg-type-error
- then
-;
-
-include scheme-primitives.4th
-
-\ }}}
-
\ ---- Read ---- {{{
variable parse-idx
'\n' parse-str parse-str-span @ + !
1 parse-str-span +! ;
+: append-eof
+ 4 parse-str parse-str-span @ + !
+ 1 parse-str-span +! ;
+
: empty-parse-str
0 parse-str-span !
0 parse-idx ! ;
: getline
- parse-str 160 expect cr
- span @ parse-str-span !
+ current-input-port obj@ console-i/o-port obj@ objeq? if
+ parse-str 160 expect cr
+ span @ parse-str-span !
+ else
+ parse-str 160 current-input-port obj@ fileport>fid read-line
+ drop swap parse-str-span !
+
+ parse-str-span @ 0= and if append-eof then
+ then
append-newline
0 parse-idx ! ;
charavailable? false = if getline then
parse-str parse-idx @ + @ ;
+: '\t' 9 ;
: whitespace? ( -- bool )
nextchar BL =
- nextchar '\n' = or ;
+ nextchar '\n' =
+ nextchar '\t' =
+ or or ;
+: EOF 4 ;
: eof? ( -- bool )
- nextchar 4 = ;
+ nextchar EOF = ;
: delim? ( -- bool )
whitespace?
realnum-type
;
-: readbool ( -- bool-atom )
+: readbool ( -- bool-obj )
inc-parse-idx
nextchar [char] f = if
boolean-type
;
-: readchar ( -- char-atom )
+: readchar ( -- char-obj )
inc-parse-idx
inc-parse-idx
then
eof? if
+ EOF character-type
inc-parse-idx
- bold fg blue ." Moriturus te saluto." reset-term cr
- quit
+ exit
then
\ Anything else is parsed as a symbol
\ }}}
-\ ---- DEBUGGING ---- {{{
+\ ---- Garbage Collection ---- {{{
-false value debug-mode
+variable gc-enabled
+false gc-enabled !
-:noname
- debug-mode if
- ." Object: " 2dup cr print cr
- ." Pairlike: " pairlike? if
- ." TRUE"
- pairlike-marked? if
- ." (Marked)"
- else
- ." (Unmarked)"
- then
- else
- ." FALSE"
- then
- cr ." [paused]"
- key drop cr
- then
-; is gc-mark-trace
+variable gc-stack-depth
-: gc-mark-sweep
- gc-unmark
- symbol-table obj@ gc-mark-obj
- global-env obj@ gc-mark-obj
- gc-sweep
+: enable-gc
+ depth gc-stack-depth !
+ true gc-enabled ! ;
+
+: disable-gc
+ false gc-enabled ! ;
+
+: gc-enabled?
+ gc-enabled @ ;
+
+: pairlike? ( obj -- obj bool )
+ pair-type istype? if true exit then
+ string-type istype? if true exit then
+ symbol-type istype? if true exit then
+ compound-proc-type istype? if true exit then
+
+ false
+;
+
+: pairlike-marked? ( obj -- obj bool )
+ over nextfrees + @ 0=
+;
+
+: mark-pairlike ( obj -- obj )
+ over nextfrees + 0 swap !
+;
+
+: gc-unmark ( -- )
+ scheme-memsize 0 do
+ 1 nextfrees i + !
+ loop
;
+: gc-mark-obj ( obj -- )
+
+ pairlike? invert if 2drop exit then
+ pairlike-marked? if 2drop exit then
+
+ mark-pairlike
+
+ drop pair-type 2dup
+
+ car recurse
+ cdr recurse
+;
+
+: gc-sweep
+ scheme-memsize nextfree !
+ 0 scheme-memsize 1- do
+ nextfrees i + @ 0<> if
+ nextfree @ nextfrees i + !
+ i nextfree !
+ then
+ -1 +loop
+;
+
+\ Following a GC, this gives the amount of free memory
: gc-count-marked
0
scheme-memsize 0 do
loop
;
+\ Debugging word - helps spot memory that is retained
: gc-zero-unmarked
scheme-memsize 0 do
nextfrees i + @ 0<> if
loop
;
+:noname
+ \ ." GC! "
+
+ gc-unmark
+
+ symbol-table obj@ gc-mark-obj
+ global-env obj@ gc-mark-obj
+
+ depth gc-stack-depth @ do
+ PSP0 i + 1 + @
+ PSP0 i + 2 + @
+
+ gc-mark-obj
+ 2 +loop
+
+ gc-sweep
+
+ \ ." (" gc-count-marked . ." pairs marked as used.)" cr
+; is collect-garbage
+
\ }}}
+\ ---- Primitives ---- {{{
+
+: make-primitive ( cfa -- )
+ bl word
+ count
+
+ \ 2dup ." Defining primitive " type ." ..." cr
+
+ cstr>charlist
+ drop symbol-type
+
+ 2dup
+
+ symbol-table obj@
+ cons
+ symbol-table obj!
+
+ rot primitive-proc-type ( var prim )
+ global-env obj@ define-var
+;
+
+: arg-count-error
+ bold fg red ." Incorrect argument count." reset-term cr
+ abort
+;
+
+: ensure-arg-count ( args n -- )
+ dup 0= if
+ drop nil objeq? false = if
+ arg-count-error
+ then
+ else
+ -rot 2dup nil objeq? if
+ arg-count-error
+ then
+
+ cdr rot 1- recurse
+ then
+;
+
+: arg-type-error
+ bold fg red ." Incorrect argument type." reset-term cr
+ abort
+;
+
+: ensure-arg-type ( arg type -- arg )
+ istype? false = if
+ arg-type-error
+ then
+;
+
+include scheme-primitives.4th
+
+\ }}}
+
+\ ---- Loading files ---- {{{
+
+: charlist>cstr ( charlist addr -- n )
+
+ dup 2swap ( origaddr addr charlist )
+
+ begin
+ 2dup nil objeq? false =
+ while
+ 2dup cdr 2swap car
+ drop ( origaddr addr charlist char )
+ -rot 2swap ( origaddr charlist addr char )
+ over !
+ 1+ -rot ( origaddr nextaddr charlist )
+ repeat
+
+ 2drop ( origaddr finaladdr )
+ swap -
+;
+
+: load ( addr n -- finalResult )
+ open-input-file
+
+ empty-parse-str
+
+ ok-symbol ( port res )
+
+ begin
+ 2over read-port ( port res obj )
+
+ 2dup EOF character-type objeq? if
+ 2drop 2swap close-port
+ exit
+ then
+
+ 2swap 2drop ( port obj )
+
+ global-env obj@ eval ( port res )
+ again
+;
+
+:noname ( args -- finalResult )
+ 2dup 1 ensure-arg-count
+ car string-type ensure-arg-type
+
+ drop pair-type
+ pad charlist>cstr
+ pad swap load
+; make-primitive load
+
+\ }}}
\ ---- REPL ----
cr ." Welcome to scheme.forth.jl!" cr
." Use Ctrl-D to exit." cr
-
empty-parse-str
+ enable-gc
+
begin
cr bold fg green ." > " reset-term
- read
+ read-console
+
+ 2dup EOF character-type objeq? if
+ bold fg blue ." Moriturus te saluto." reset-term cr
+ exit
+ then
global-env obj@ eval
The Lambda Lab / projects / scheme.forth.jl.git / blobdiff