trying to get in abort-current-continuation

js-assembler/assemble.rkt

@@ -559,8 +559,7 @@ EOF
                     (assemble-label (make-Label (LinkedLabel-label label)))])))]
       
       [(PushControlFrame/Prompt? stmt)
-       ;; fixme: use a different frame structure
-       (format "M.c.push(new RT.PromptFrame(~a,~a));" 
+       (format "M.c.push(new RT.PromptFrame(~a,~a,M.e.length,false));" 
                (let: ([label : (U Symbol LinkedLabel) (PushControlFrame/Prompt-label stmt)])
                  (cond
                    [(symbol? label) 

js-assembler/runtime-src/baselib-frames.js

@@ -40,11 +40,15 @@
 
 
 
-    // A prompt frame includes a return address, as well as a prompt tag
-    // for supporting delimited continuations.
-    var PromptFrame = function(label, tag) {
+    // A prompt frame includes a return address, as well as a prompt
+    // tag for supporting delimited continuations.  To support abort,
+    // we also keep the size of the environment, and the handler
+    // to call if an abort happens.
+    var PromptFrame = function(label, tag, envLength, handler) {
 	this.label = label;
 	this.tag = tag; // ContinuationPromptTag
+        this.envLength = envLength;
+        this.handler = handler;
     };
     PromptFrame.prototype = baselib.heir(Frame.prototype);
 

js-assembler/runtime-src/baselib-primitives.js

@@ -114,9 +114,19 @@
     var checkHash = baselib.check.checkHash;
     var checkMutableHash = baselib.check.checkMutableHash;
     var checkImmutableHash = baselib.check.checkImmutableHash;
-    var checkAny = baselib.check.makeCheckArgumentType(
-        function(x) { return true; },
-        'any');
+
+    // Just for consistency with the other names, we provide checkAny, which
+    // doesn't really do any checking.
+    var checkAny = function(M, name, offset) {
+        return M.e[M.e.length-1-offset];
+    };
+
+    var checkPromptTag = baselib.check.makeCheckArgumentType(
+        baselib.contmarks.isContinuationPromptTag,
+        'prompt tag');
+
+    var PromptFrame = baselib.frames.PromptFrame;
+
     //////////////////////////////////////////////////////////////////////
 
 
@@ -3135,6 +3145,45 @@
         });
 
 
+    installPrimitiveClosure(
+        'abort-current-continuation',
+        2, //baselib.arity.makeArityAtLeast(1),
+        function(M) {
+            var promptTag = checkPromptTag(M, 'abort-current-continuation', 0);
+            var vals = [];
+            var frame;
+            for(i = 1; i < M.a; i++) {
+                vals.push(M.e[M.e.length-1-i]);
+            }
+            
+            // First, find the continuation prompt.
+            while(true) {
+                frame = M.c.pop();
+                if (frame instanceof PromptFrame) {
+                    break;
+                }
+            }
+            // Shrink the environment to what was observed when the PromptFrame was installed.
+            M.e.length = frame.envLength;
+
+            // Default behavior:
+            // Re-establish the prompt frame and call the thunk.
+            // FIXME: generalize to different handlers!
+            M.e.push(c);
+            if (isProcedure(vals[0])) {
+                M.p = vals[0];
+                M.a = 0;
+                baselib.functions.rawApply(M);
+            } else {
+                raiseArgumentTypeError(M,
+                                       'abort-current-continuation',
+                                       'thunk',
+                                       1,
+                                       vals[0]);
+            }
+        });
+
+
 
 
     exports['Primitives'] = Primitives;

lang/kernel.rkt

@@ -228,6 +228,8 @@
          current-inexact-milliseconds
          current-seconds
          
+
+         abort-current-continuation
          
          ;; needed for cs019-local
          #%stratified-body

web-world/google-maps/google-maps.rkt

@@ -0,0 +1,13 @@
+#lang s-exp "../../lang/base.rkt"
+
+(require "../../js.rkt")
+
+(provide load-gmaps-library)
+
+
+(define (load-gmaps-library api-key with-sensor)
+  (load-script (string-append
+                "http://maps.googleapis.com/maps/api/js?key="
+                api-key
+                "&sensor="
+                (if with-sensor "true" "false"))))