X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Fscheme.4th;h=7d9e2c40f55c5688863a38b14f0f7e7d8129ee82;hb=84e8f70df686212cbf4c4d38b282651a3735f840;hp=ec97f09761c26f8603c14001277cd08b6f5e7dd8;hpb=724ff46a1b082bef48b310a85d5a82037c2a914c;p=scheme.forth.jl.git

diff --git a/src/scheme.4th b/src/scheme.4th
index ec97f09..7d9e2c4 100644
--- a/src/scheme.4th
+++ b/src/scheme.4th
@@ -3,6 +3,7 @@ scheme definitions
 
 include term-colours.4th
 include defer-is.4th
+include goto.4th
 include catch-throw.4th
 include integer.4th
 include float.4th
@@ -11,6 +12,7 @@ include debugging.4th
 
 defer read
 defer expand
+defer analyze
 defer eval
 defer print
 
@@ -162,6 +164,10 @@ variable nextfree
     R> R>
 ;
 
+: 2pick ( an bn an-1 bn-1 ... a0 b0 n -- an bn an-1 bn-1 ... a0 b0 an bn )
+    2* 1+ dup
+    >R pick R> pick ;
+
 \ }}}
 
 \ ---- Pre-defined symbols ---- {{{
@@ -1726,6 +1732,133 @@ hide env
 
 \ }}}
 
+\ ---- Analyze ----
+
+: evaluate-eproc ( env eproc --- res )
+    begin
+        nil? invert
+    while
+        2dup car
+        2swap cdr
+    repeat
+    
+    2drop \ get rid of null
+
+    \ Final element of eproc list is primitive procedure
+    drop \ dump type signifier
+    goto \ jump straight to primitive procedure (executor)
+;
+
+: self-evaluating-executor ( env exp -- exp )
+    2swap 2drop ;
+
+: analyze-self-evaluating ( exp --- eproc )
+    ['] self-evaluating-executor primitive-proc-type
+    nil cons cons
+;
+
+: quote-executor ( env exp -- exp )
+    2swap 2drop ;
+
+: analyze-quoted ( exp -- eproc )
+    quote-body
+
+    ['] quote-executor primitive-proc-type
+    nil cons cons
+;
+
+: variable-executor ( env var -- val )
+    2swap lookup-var ;
+
+: analyze-variable ( exp -- eproc )
+    ['] variable-executor primitive-proc-type
+    nil cons cons
+;
+
+: definition-executor ( env var val-eproc -- ok )
+     2rot 2dup 2rot ( var env env val-eproc )
+    evaluate-eproc 2swap ( var val env )
+    define-var
+    ok-symbol
+;
+
+: analyze-definition ( exp -- eproc )
+    2dup definition-var
+    2swap definition-val analyze
+
+    ['] definition-executor primitive-proc-type
+    nil cons cons cons
+;
+
+: assignment-executor ( env var val-eproc -- ok )
+    2rot 2dup 2rot ( var env env val-eproc )
+    evaluate-eproc 2swap ( var val env )
+    set-var
+    ok-symbol
+;
+
+: analyze-assignment ( exp -- eproc )
+    2dup assignment-var
+    2swap assignment-val analyze ( var val-eproc )
+
+    ['] assignment-executor primitive-proc-type
+    nil cons cons cons
+;
+
+: if-executor ( env pproc cproc aproc -- res )
+    2rot 3 2pick 2swap ( env cproc aproc env pproc )
+    evaluate-eproc
+    true? if
+        2drop evaluate-eproc
+    else
+        2swap 2drop evaluate-eproc
+    then
+;
+
+: analyze-if ( exp -- eproc )
+    2dup if-predicate analyze
+    2swap 2dup if-consequent analyze
+    2swap if-alternative analyze
+
+    ['] if-executor primitive-proc-type
+    nil cons cons cons cons
+;
+
+:noname ( exp --- eproc )
+
+    self-evaluating? if
+        analyze-self-evaluating
+        exit
+    then
+
+    quote? if
+        analyze-quoted
+        exit
+    then
+    
+    variable? if
+        analyze-variable
+        exit
+    then
+
+    definition? if
+        analyze-definition
+        exit
+    then
+
+    assignment? if
+        analyze-assignment
+        exit
+    then
+
+    if? if
+        analyze-if
+        exit
+    then
+
+; is analyze
+
+
 \ ---- Macro Expansion ---- {{{
 
 ( Simply evaluates the given procedure with expbody as its argument. )
@@ -2110,7 +2243,7 @@ variable gc-stack-depth
 
     include scheme-primitives.4th
 
-    s" scheme-library.scm" load 2drop
+    \ s" scheme-library.scm" load 2drop
     
 \ }}}
 
@@ -2143,7 +2276,7 @@ variable gc-stack-depth
     enable-gc
 
     \ Display welcome message
-    welcome-symbol nil cons global-env obj@ eval 2drop
+    \ welcome-symbol nil cons global-env obj@ eval 2drop
 
     begin
         ['] repl-body catch