X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=scheme.4th;h=136c8a85b3abec94c7ef9a86f5a04de4d1f0ff3d;hb=77eccf994da4cc6b875bcfe479d069153dd8158c;hp=1796ea19631ff2bbad3907e675a53c2a722b5f9c;hpb=c77b9cc08b9169c4d08633d320df9684f67938b1;p=scheme.forth.jl.git diff --git a/scheme.4th b/scheme.4th index 1796ea1..136c8a8 100644 --- a/scheme.4th +++ b/scheme.4th @@ -28,10 +28,12 @@ make-type boolean-type make-type character-type make-type string-type make-type nil-type +make-type none-type make-type pair-type make-type symbol-type make-type primitive-proc-type make-type compound-proc-type +make-type fileport-type : istype? ( obj type -- obj bool ) over = ; @@ -111,6 +113,9 @@ variable nextfree : nil 0 nil-type ; : nil? nil-type istype? ; +: none 0 none-type ; +: none? none-type istype? ; + : objvar create nil swap , , ; : value@ ( objvar -- val ) @ ; @@ -139,6 +144,36 @@ variable nextfree \ }}} +\ ---- Port I/O ---- {{{ + +: fileport>fid ( fileport -- fid ) + drop ; + +: fid>fileport ( fid -- fileport ) + fileport-type ; + +: open-input-file ( addr n -- fileport ) + r/o open-file drop fid>fileport +; + +: close-port ( fileport -- ) + fileport>fid close-file drop +; + +objvar console-i/o-port +0 fileport-type console-i/o-port obj! + +objvar current-input-port +console-i/o-port obj@ current-input-port obj! + +: read-port ( fileport -- obj ) + current-input-port obj! + read ; + +: read-console ( -- obj ) + console-i/o-port obj@ read-port ; + +\ }}} \ ---- Pre-defined symbols ---- {{{ @@ -204,7 +239,7 @@ objvar symbol-table ; -: (create-symbol) ( addr n -- symbol-obj ) +: cstr>charlist ( addr n -- symbol-obj ) dup 0= if 2drop nil else @@ -220,7 +255,7 @@ objvar symbol-table bl word count - (create-symbol) + cstr>charlist drop symbol-type 2dup @@ -240,6 +275,7 @@ create-symbol ok ok-symbol create-symbol if if-symbol create-symbol lambda lambda-symbol create-symbol λ λ-symbol +create-symbol begin begin-symbol \ }}} @@ -361,61 +397,6 @@ global-env obj! \ }}} -\ ---- 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 @@ -444,13 +425,24 @@ parse-idx-stack parse-idx-sp ! '\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 ! ; @@ -467,12 +459,16 @@ parse-idx-stack parse-idx-sp ! 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? @@ -867,9 +863,9 @@ parse-idx-stack parse-idx-sp ! 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 @@ -894,6 +890,7 @@ parse-idx-stack parse-idx-sp ! character-type istype? if true exit then string-type istype? if true exit then nil-type istype? if true exit then + none-type istype? if true exit then false ; @@ -1016,6 +1013,38 @@ parse-idx-stack parse-idx-sp ! drop compound-proc-type ; +: begin? ( obj -- obj bool ) + begin-symbol tagged-list? ; + +: begin-actions ( obj -- actions ) + cdr ; + +: eval-sequence ( explist env -- finalexp env ) + ( Evaluates all bar the final expressions in + an an expression list. The final expression + is returned to allow for tail optimization. ) + + 2swap ( env explist ) + + \ Abort on empty list + 2dup nil objeq? if + 2drop none + 2swap exit + then + + begin + 2dup cdr ( env explist nextexplist ) + 2dup nil objeq? false = + while + -2rot car 2over ( nextexplist env exp env ) + eval + 2drop \ discard result + 2swap ( env nextexplist ) + repeat + + 2drop car 2swap ( finalexp env ) +; + : application? ( obj -- obj bool) pair-type istype? ; @@ -1068,19 +1097,7 @@ parse-idx-stack parse-idx-sp ! extend-env ( body env ) - 2swap ( env body ) - - begin - 2dup cdr 2dup nil objeq? false = - while - -2rot car 2over ( nextbody env exp env ) - eval - 2drop \ discard result - 2swap ( env nextbody ) - repeat - - 2drop ( env body ) - car 2swap ( exp env ) + eval-sequence R> drop ['] eval goto-deferred \ Tail call optimization endof @@ -1141,6 +1158,12 @@ parse-idx-stack parse-idx-sp ! exit then + begin? if + begin-actions 2swap + eval-sequence + ['] eval goto-deferred + then + application? if 2over 2over operator 2swap eval @@ -1225,6 +1248,9 @@ parse-idx-stack parse-idx-sp ! : printcomp ( primobj -- ) 2drop ." " ; +: printnone ( noneobj -- ) + 2drop ." Unspecified return value" ; + :noname ( obj -- ) fixnum-type istype? if printfixnum exit then realnum-type istype? if printrealnum exit then @@ -1236,6 +1262,7 @@ parse-idx-stack parse-idx-sp ! pair-type istype? if ." (" printpair ." )" exit then primitive-proc-type istype? if printprim exit then compound-proc-type istype? if printcomp exit then + none-type istype? if printnone exit then bold fg red ." Error printing expression - unrecognized type. Aborting" reset-term cr abort @@ -1346,20 +1373,132 @@ variable gc-stack-depth \ }}} +\ ---- 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 ---- : 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 + 2drop + bold fg blue ." Moriturus te saluto." reset-term cr + exit + then global-env obj@ eval