X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=scheme.4th;h=8c5b159026782db9952cce2f45fce954e670e49b;hb=7bea53082737088667ae438fcdba69137c43674d;hp=26a7a85618d9c5b6593a80299513e4b1ba058736;hpb=6283b0778b4e81acdd3d6009ddfe197cb6b9eb69;p=scheme.forth.jl.git diff --git a/scheme.4th b/scheme.4th index 26a7a85..8c5b159 100644 --- a/scheme.4th +++ b/scheme.4th @@ -37,7 +37,7 @@ make-type fileport-type : istype? ( obj type -- obj bool ) over = ; -\ ------ List-structured memory ------ {{{ +\ ---- List-structured memory ---- {{{ 10000 constant scheme-memsize @@ -180,7 +180,7 @@ console-i/o-port obj@ current-input-port obj! objvar symbol-table : duplicate-charlist ( charlist -- copy ) - 2dup nil objeq? false = if + nil? false = if 2dup car 2swap cdr recurse cons then ; @@ -268,14 +268,15 @@ objvar symbol-table does> dup @ swap 1+ @ ; -create-symbol quote quote-symbol -create-symbol define define-symbol -create-symbol set! set!-symbol -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 +create-symbol quote quote-symbol +create-symbol define define-symbol +create-symbol define-macro define-macro-symbol +create-symbol set! set!-symbol +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 \ }}} @@ -335,7 +336,7 @@ objvar vals : get-vars-vals ( var env -- vars? vals? bool ) begin - 2dup nil objeq? false = + nil? false = while 2over 2over first-frame get-vars-vals-frame if @@ -391,12 +392,73 @@ objvar env hide env +: make-procedure ( params body env -- proc ) + nil + cons cons cons + drop compound-proc-type +; + objvar global-env nil nil nil extend-env global-env obj! \ }}} +\ ---- Macros ---- {{{ + +objvar macro-table + +( Look up macro in macro table. Returns nil if + no macro is found. ) +: lookup-macro ( name_symbol -- proc ) + macro-table obj@ + + begin + nil? false = + while + 2over 2over + car car objeq? if + 2swap 2drop + car cdr + exit + then + + cdr + repeat + + 2swap 2drop +; + +: make-macro ( name_symbol params body env -- ) + make-procedure + + 2swap ( proc name_symbol ) + + macro-table obj@ + + begin + nil? false = + while + 2over 2over ( proc name table name table ) + car car objeq? if + 2swap 2drop ( proc table ) + car ( proc entry ) + set-cdr! + exit + then + + cdr + repeat + + 2drop + + 2swap cons + macro-table obj@ cons + macro-table obj! +; + +\ }}} + \ ---- Read ---- {{{ variable parse-idx @@ -970,6 +1032,34 @@ parse-idx-stack parse-idx-sp ! ok-symbol ; +: macro-definition? ( obj -- obj bool ) + define-macro-symbol tagged-list? ; + +: macro-definition-name ( exp -- mname ) + cdr car car ; + +: macro-definition-params ( exp -- params ) + cdr car cdr ; + +: macro-definition-body ( exp -- body ) + cdr cdr ; + +objvar env +: eval-define-macro ( obj env -- res ) + env obj! + + 2dup macro-definition-name 2swap ( name obj ) + 2dup macro-definition-params 2swap ( name params obj ) + macro-definition-body ( name params body ) + + env obj@ ( name params body env ) + + make-macro + + ok-symbol +; +hide env + : if? ( obj -- obj bool ) if-symbol tagged-list? ; @@ -981,7 +1071,7 @@ parse-idx-stack parse-idx-sp ! : if-alternative ( ifobj -- alt|false ) cdr cdr cdr - 2dup nil objeq? if + nil? if 2drop false else car @@ -1007,12 +1097,6 @@ parse-idx-stack parse-idx-sp ! : lambda-body ( obj -- body ) cdr cdr ; -: make-procedure ( params body env -- proc ) - nil - cons cons cons - drop compound-proc-type -; - : begin? ( obj -- obj bool ) begin-symbol tagged-list? ; @@ -1027,14 +1111,14 @@ parse-idx-stack parse-idx-sp ! 2swap ( env explist ) \ Abort on empty list - 2dup nil objeq? if + nil? if 2drop none 2swap exit then begin 2dup cdr ( env explist nextexplist ) - 2dup nil objeq? false = + nil? false = while -2rot car 2over ( nextexplist env exp env ) eval @@ -1045,7 +1129,7 @@ parse-idx-stack parse-idx-sp ! 2drop car 2swap ( finalexp env ) ; -: application? ( obj -- obj bool) +: application? ( obj -- obj bool ) pair-type istype? ; : operator ( obj -- operator ) @@ -1160,6 +1244,11 @@ parse-idx-stack parse-idx-sp ! exit then + macro-definition? if + 2swap eval-define-macro + exit + then + if? if 2over 2over if-predicate @@ -1189,12 +1278,32 @@ parse-idx-stack parse-idx-sp ! then application? if - 2over 2over - operator 2swap eval - -2rot - operands 2swap list-of-vals - apply + 2over 2over ( env exp env exp ) + operator 2dup ( env exp env opname opname ) + + lookup-macro nil? if + \ Regular function application + + 2drop ( env exp env opname ) + + 2swap eval ( env exp proc ) + -2rot ( proc env exp ) + operands 2swap ( proc operands env ) + list-of-vals ( proc argvals ) + + apply + else + \ Macro function evaluation + + ." Macro eval" + + ( env exp env opname mproc ) + 2swap 2drop -2rot 2drop cdr ( env mproc body ) + + \ TODO: evaluate macro procedure on expression body + ." ABORTED: Macros not yet fully implemented!" abort + then exit then @@ -1381,6 +1490,7 @@ variable gc-stack-depth gc-unmark symbol-table obj@ gc-mark-obj + macro-table obj@ gc-mark-obj global-env obj@ gc-mark-obj depth gc-stack-depth @ do @@ -1429,7 +1539,7 @@ variable gc-stack-depth arg-count-error then else - -rot 2dup nil objeq? if + -rot nil? if arg-count-error then @@ -1459,7 +1569,7 @@ include scheme-primitives.4th dup 2swap ( origaddr addr charlist ) begin - 2dup nil objeq? false = + nil? false = while 2dup cdr 2swap car drop ( origaddr addr charlist char )