X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=scheme.4th;h=ae88b4b44d746e824a9cd0c4e6e29ae49e0a24d6;hb=9ad6e6f21fbbefe9e38bc6b4b8d2a78f8cbca229;hp=1953cf98cf0ec004d9bbbe7c4a54acc96b93d4f6;hpb=dc6e0cea1e1e982da8029c94d78ee66ab7e8fd82;p=scheme.forth.jl.git

diff --git a/scheme.4th b/scheme.4th
index 1953cf9..ae88b4b 100644
--- a/scheme.4th
+++ b/scheme.4th
@@ -103,6 +103,66 @@ variable nextfree
 
 objvar symbol-table
 
+: duplicate-charlist ( charlist -- copy )
+    2dup nil objeq? false = if
+        2dup car 2swap cdr recurse cons
+    then ;
+
+: charlist-equiv ( charlist charlist -- bool )
+
+    2over 2over
+
+    \ One or both nil
+    nil? -rot 2drop
+    if
+        nil? -rot 2drop
+        if
+            2drop 2drop true exit
+        else
+            2drop 2drop false exit
+        then
+    else
+        nil? -rot 2drop
+        if
+            2drop 2drop false exit
+        then
+    then
+
+    2over 2over
+
+    \ Neither nil
+    car drop -rot car drop = if
+            cdr 2swap cdr recurse
+        else
+            2drop 2drop false
+    then
+;
+
+: charlist>symbol ( charlist -- symbol-obj )
+
+    symbol-table fetchobj
+
+    begin
+        nil? false =
+    while
+        2over 2over
+        car drop pair-type
+        charlist-equiv if
+            2swap 2drop
+            car
+            exit
+        else
+            cdr
+        then
+    repeat
+
+    2drop
+    drop symbol-type 2dup
+    symbol-table fetchobj cons
+    symbol-table setobj
+;
+
+
 : (create-symbol) ( addr n -- symbol-obj )
     dup 0= if
         2drop nil
@@ -296,6 +356,17 @@ global-env setobj
     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
 
 \ }}}
@@ -366,12 +437,27 @@ parse-idx-stack parse-idx-sp !
     nextchar [char] ) = or
 ;
 
+: commentstart? ( -- bool )
+    nextchar [char] ; = ;
+
 : eatspaces
+
+    false \ Indicates whether or not we're eating a comment
+
     begin
-        whitespace?
+        dup whitespace? or commentstart? or
     while
+        dup nextchar '\n' = and if
+            invert \ Stop eating comment
+        else
+            dup false = commentstart? and if   
+                invert \ Begin eating comment
+            then
+        then
+
         inc-parse-idx
     repeat
+    drop
 ;
 
 : digit? ( -- bool )
@@ -382,8 +468,11 @@ parse-idx-stack parse-idx-sp !
 : minus? ( -- bool )
     nextchar [char] - = ;
 
+: plus? ( -- bool )
+    nextchar [char] + = ;
+
 : fixnum? ( -- bool )
-    minus? if
+    minus? plus? or if
         inc-parse-idx
 
         delim? if
@@ -482,8 +571,11 @@ parse-idx-stack parse-idx-sp !
     nextchar [char] " = ;
 
 : readnum ( -- num-atom )
-    minus? dup if
+    plus? minus? or if
+        minus?
         inc-parse-idx
+    else
+        false
     then
 
     0
@@ -567,60 +659,6 @@ parse-idx-stack parse-idx-sp !
     cons
 ;
 
-: charlist-equiv ( charlist charlist -- bool )
-
-    2over 2over
-
-    \ One or both nil
-    nil? -rot 2drop
-    if
-        nil? -rot 2drop
-        if
-            2drop 2drop true exit
-        else
-            2drop 2drop false exit
-        then
-    else
-        nil? -rot 2drop
-        if
-            2drop 2drop false exit
-        then
-    then
-
-    2over 2over
-
-    \ Neither nil
-    car drop -rot car drop = if
-            cdr 2swap cdr recurse
-        else
-            2drop 2drop false
-    then
-;
-
-: charlist>symbol ( charlist -- symbol-obj )
-
-    symbol-table fetchobj
-
-    begin
-        nil? false =
-    while
-        2over 2over
-        car drop pair-type
-        charlist-equiv if
-            2swap 2drop
-            car
-            exit
-        else
-            cdr
-        then
-    repeat
-
-    2drop
-    drop symbol-type 2dup
-    symbol-table fetchobj cons
-    symbol-table setobj
-;
-
 : readpair ( -- pairobj )
     eatspaces
 
@@ -724,6 +762,7 @@ parse-idx-stack parse-idx-sp !
     then
 
     eof? if
+        inc-parse-idx
         bold fg blue ." Moriturus te saluto." reset-term ."  ok" cr
         quit
     then