forth: [, ], STATE, EVALUATE (+5; Hayes 463→477, 74%)

lib/forth/compiler.sx

@@ -649,10 +649,13 @@
         (s)
         (let
           ((addr (forth-pop s)))
-          (if
-            (string? addr)
-            (forth-push s (or (get (get s "vars") addr) 0))
-            (forth-push s (forth-mem-read s addr))))))
+          (cond
+            ((= addr "@@state")
+              (forth-push s (if (get s "compiling") -1 0)))
+            ((= addr "@@in") (forth-push s 0))
+            ((string? addr)
+              (forth-push s (or (get (get s "vars") addr) 0)))
+            (else (forth-push s (forth-mem-read s addr)))))))
     (forth-def-prim!
       state
       "!"
@@ -788,6 +791,31 @@
         (let
           ((w (forth-pop s)))
           (forth-push s (or (get w "body-addr") 0)))))
+    (forth-def-prim-imm!
+      state
+      "["
+      (fn (s) (dict-set! s "compiling" false)))
+    (forth-def-prim! state "]" (fn (s) (dict-set! s "compiling" true)))
+    (forth-def-prim! state "STATE" (fn (s) (forth-push s "@@state")))
+    (forth-def-prim!
+      state
+      "EVALUATE"
+      (fn
+        (s)
+        (let
+          ((u (forth-pop s)) (addr (forth-pop s)))
+          (let
+            ((src (forth-mem-read-string s addr u)))
+            (let
+              ((saved-input (get s "input")))
+              (dict-set! s "input" (forth-tokens src))
+              (forth-interpret-loop s)
+              (dict-set! s "input" saved-input))))))
+    (forth-def-prim!
+      state
+      "SOURCE"
+      (fn (s) (forth-push s 0) (forth-push s 0)))
+    (forth-def-prim! state ">IN" (fn (s) (forth-push s "@@in")))
     (forth-def-prim!
       state
       "WORD"