X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=scheme.4th;h=3ea9d66e0598c0513ecc2595c0c202b8e3085a0f;hb=c1614af3cb919d99081fb11d7ba2c1a83cb2d408;hp=8bc44d3ad9693c76273660e20f42cac8b5ac9941;hpb=215a272cf2521c34e9f8d2be62db1a35ac0a9809;p=scheme.forth.jl.git diff --git a/scheme.4th b/scheme.4th index 8bc44d3..3ea9d66 100644 --- a/scheme.4th +++ b/scheme.4th @@ -3,7 +3,9 @@ scheme definitions include term-colours.4th include defer-is.4th -include catch-throw.4th +include float.4th + +include debugging.4th defer read defer eval @@ -11,15 +13,23 @@ defer print \ ------ Types ------ -0 constant fixnum-type -1 constant boolean-type -2 constant character-type -3 constant string-type -4 constant nil-type -5 constant pair-type -6 constant symbol-type -7 constant primitive-proc-type -8 constant compound-proc-type +variable nexttype +0 nexttype ! +: make-type + create nexttype @ , + 1 nexttype +! + does> @ ; + +make-type fixnum-type +make-type realnum-type +make-type boolean-type +make-type character-type +make-type string-type +make-type nil-type +make-type pair-type +make-type symbol-type +make-type primitive-proc-type +make-type compound-proc-type : istype? ( obj type -- obj bool ) over = ; @@ -31,9 +41,20 @@ create car-type-cells N allot create cdr-cells N allot create cdr-type-cells N allot +create nextfrees N allot +:noname + N 0 do + i 1+ nextfrees i + ! + loop +; execute + variable nextfree 0 nextfree ! +: inc-nextfree + nextfrees nextfree @ + @ + nextfree ! ; + : cons ( car-obj cdr-obj -- pair-obj ) cdr-type-cells nextfree @ + ! cdr-cells nextfree @ + ! @@ -41,8 +62,7 @@ variable nextfree car-cells nextfree @ + ! nextfree @ pair-type - - 1 nextfree +! + inc-nextfree ; : car ( pair-obj -- car-obj ) @@ -105,6 +125,64 @@ variable nextfree \ }}} +\ ---- Garbage Collection ---- {{{ + +variable gc-enabled +false gc-enabled ! + +: gc-enable + true gc-enabled ! ; + +: gc-disable + 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-mark-obj ( obj -- ) + + pairlike? if + pairlike-marked? if 2drop exit then + + mark-pairlike + + 2dup + + car recurse + cdr recurse + else + 2drop + then +; + +: gc-sweep + N nextfree ! + 0 N 1- do + nextfrees i + @ 0<> if + nextfree @ nextfrees i + ! + i nextfree ! + then + -1 +loop ; + +\ }}} + \ ---- Pre-defined symbols ---- {{{ objvar symbol-table @@ -332,6 +410,8 @@ global-env obj! bl word count + \ 2dup ." Defining primitive " type ." ..." cr + (create-symbol) drop symbol-type @@ -500,13 +580,52 @@ parse-idx-stack parse-idx-sp ! inc-parse-idx repeat - delim? if - pop-parse-idx - true - else - pop-parse-idx - false + delim? pop-parse-idx +; + +: realnum? ( -- bool ) + push-parse-idx + + minus? plus? or if + inc-parse-idx + then + + \ Record starting parse idx: + \ Want to detect whether any characters (following +/-) were eaten. + parse-idx @ + + begin digit? while + inc-parse-idx + repeat + + [char] . nextchar = if + inc-parse-idx + begin digit? while + inc-parse-idx + repeat + then + + [char] e nextchar = [char] E nextchar = or if + inc-parse-idx + + minus? plus? or if + inc-parse-idx + then + + digit? invert if + drop pop-parse-idx false exit + then + + begin digit? while + inc-parse-idx + repeat then + + \ This is a real number if characters were + \ eaten and the next characer is a delimiter. + parse-idx @ < delim? and + + pop-parse-idx ; : boolean? ( -- bool ) @@ -576,7 +695,7 @@ parse-idx-stack parse-idx-sp ! : string? ( -- bool ) nextchar [char] " = ; -: readnum ( -- num-atom ) +: readfixnum ( -- num-atom ) plus? minus? or if minus? inc-parse-idx @@ -596,6 +715,24 @@ parse-idx-stack parse-idx-sp ! fixnum-type ; +: readrealnum ( -- realnum ) + + \ Remember that at this point we're guaranteed to + \ have a parsable real on this line. + + parse-str parse-idx @ + + + begin delim? false = while + inc-parse-idx + repeat + + parse-str parse-idx @ + over - + + float-parse + + realnum-type +; + : readbool ( -- bool-atom ) inc-parse-idx @@ -713,7 +850,12 @@ parse-idx-stack parse-idx-sp ! eatspaces fixnum? if - readnum + readfixnum + exit + then + + realnum? if + readrealnum exit then @@ -769,7 +911,7 @@ parse-idx-stack parse-idx-sp ! eof? if inc-parse-idx - bold fg blue ." Moriturus te saluto." reset-term ." ok" cr + bold fg blue ." Moriturus te saluto." reset-term cr quit then @@ -791,6 +933,7 @@ parse-idx-stack parse-idx-sp ! : self-evaluating? ( obj -- obj bool ) boolean-type istype? if true exit then fixnum-type istype? if true exit then + realnum-type istype? if true exit then character-type istype? if true exit then string-type istype? if true exit then nil-type istype? if true exit then @@ -1059,7 +1202,9 @@ parse-idx-stack parse-idx-sp ! \ ---- Print ---- {{{ -: printnum ( numobj -- ) drop 0 .R ; +: printfixnum ( fixnumobj -- ) drop 0 .R ; + +: printrealnum ( realnumobj -- ) drop float-print ; : printbool ( numobj -- ) drop if @@ -1124,7 +1269,8 @@ parse-idx-stack parse-idx-sp ! 2drop ." " ; :noname ( obj -- ) - fixnum-type istype? if printnum exit then + fixnum-type istype? if printfixnum exit then + realnum-type istype? if printrealnum exit then boolean-type istype? if printbool exit then character-type istype? if printchar exit then string-type istype? if printstring exit then @@ -1146,12 +1292,15 @@ parse-idx-stack parse-idx-sp ! cr ." Welcome to scheme.forth.jl!" cr ." Use Ctrl-D to exit." cr + empty-parse-str begin cr bold fg green ." > " reset-term read + global-env obj@ eval + fg cyan ." ; " print reset-term again ;