X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=scheme.4th;h=57ee1e66a740c7c28678f6038e2869e879cec8b5;hb=a9e0195cd866692844586002f1614ff74a79426a;hp=3728257eb997f7203c541dcadd0c885a0da1edec;hpb=9be58bf752f3b2c5b0b6c6880f77b482e9da0ffd;p=scheme.forth.jl.git diff --git a/scheme.4th b/scheme.4th index 3728257..57ee1e6 100644 --- a/scheme.4th +++ b/scheme.4th @@ -1022,43 +1022,25 @@ parse-idx-stack parse-idx-sp ! : make-lambda ( params body -- lambda-exp ) lambda-symbol -2rot cons cons ; -( Handles recursive expansion of defines in +( Handles iterative expansion of defines in terms of nested lambdas. Most Schemes only - handle one level of expansion! ) -: (definition-var-val) ( val var -- val' var' ) - symbol-type istype? if 2swap car 2swap exit then + handle one iteration of expansion! ) +: definition-var-val ( obj -- var val ) - 2dup cdr 2swap car - symbol-type istype? if - 2swap ( body procname procargs ) - 2rot ( procname procargs body ) - make-lambda ( procname lambda-exp ) - 2swap - exit - then + cdr 2dup cdr 2swap car ( val var ) - ( body procargs nextval ) - -2rot 2swap ( nextval procargs body ) - make-lambda nil cons ( nextval lambda-exp ) - 2swap ( lambda-exp nextval ) - recurse -; + begin + symbol-type istype? false = + while + 2dup cdr 2swap car ( val formals var' ) + -2rot 2swap ( var' formals val ) + make-lambda nil cons ( var' val' ) + 2swap ( val' var' ) + repeat -: definition-var-val ( obj -- var val ) - cdr 2dup cdr 2swap car - (definition-var-val) - 2swap + 2swap car ; -: assignment? ( obj -- obj bool ) - set!-symbol tagged-list? ; - -: assignment-var ( obj -- var ) - cdr car ; - -: assignment-val ( obj -- val ) - cdr cdr car ; - : eval-definition ( obj env -- res ) 2dup 2rot ( env env obj ) definition-var-val ( env env var val ) @@ -1069,7 +1051,16 @@ parse-idx-stack parse-idx-sp ! ok-symbol ; + +: assignment? ( obj -- obj bool ) + set!-symbol tagged-list? ; + +: assignment-var ( obj -- var ) + cdr car ; +: assignment-val ( obj -- val ) + cdr cdr car ; + : eval-assignment ( obj env -- res ) 2swap 2over 2over ( env obj env obj ) @@ -1639,7 +1630,7 @@ variable gc-stack-depth include scheme-primitives.4th - s" scheme-library.scm" load 2drop + \ s" scheme-library.scm" load 2drop \ }}}