debugging pause

examples/logo.rkt

@@ -0,0 +1,5 @@
+#lang planet dyoo/whalesong
+
+(require (planet dyoo/whalesong/image))
+
+(image-url "http://racket-lang.org/logo.png")

image/private/js-impl.js

@@ -1,10 +1,6 @@
-var checkString = plt.baselib.check.makeCheckArgumentType(
+var checkString = plt.baselib.check.checkString;
-    plt.baselib.strings.isString,
+var checkByte = plt.baselib.check.checkByte;
-    'string');
+var checkReal = plt.baselib.check.checkReal;
-
-var checkByte = plt.baselib.check.makeCheckArgumentType(
-    plt.baselib.numbers.isByte,
-    'byte');
 
 var checkColor = plt.baselib.check.makeCheckArgumentType(
     isColorOrColorString,
@@ -14,9 +10,9 @@ var checkImage = plt.baselib.check.makeCheckArgumentType(
     isImage,
     'image');
 
-var checkReal = plt.baselib.check.makeCheckArgumentType(
+
-    plt.baselib.numbers.isReal,
+var Closure = plt.baselib.functions.Closure;
-    'real');
+var PAUSE = plt.runtime.PAUSE;
 
 
 
@@ -34,7 +30,6 @@ EXPORTS['image-color?'] =
 
 
 
-
 EXPORTS['text'] =
     plt.baselib.functions.makePrimitiveProcedure(
         'text',
@@ -60,20 +55,44 @@ EXPORTS['text'] =
 //             ...
 //         });
 
-// FIXME
-// EXPORTS['image-url'] = 
-//     plt.baselib.functions.makePrimitiveProcedure(
-//         'image-url',
-//             ???,
-//         function(MACHINE) {
-//             ...
-//         });
 
 // FIXME
+EXPORTS['image-url'] = 
+    new Closure(
+        function(MACHINE) {
+            var url = checkString(MACHINE, 'image-url', 0);
+            PAUSE(function(restart) {
+                    var rawImage = new Image();
+                    rawImage.onload = function() {
+                        restart(function(MACHINE) {
+                            finalizeClosureCall(
+                                makeFileImage(
+                                    path.toString(),
+                                    rawImage));
+                    })
+                    });
+                rawImage.onerror = 
+                    (function(e) {
+                        restart(function(MACHINE) {
+                            plt.baselib.exceptions.raise(
+                                MACHINE, 
+                                new Error(plt.baselib.format.format(
+                                    "unable to load: ~a",
+                                    url)));
+                        });
+                    });
+                rawImage.src = path.toString();
+            );
+        },
+        1,
+        [],
+        'image-url');
+
+// // FIXME
 // EXPORTS['open-image-url'] = 
 //     plt.baselib.functions.makePrimitiveProcedure(
 //         'open-image-url',
-//             ???,
+//         1,
 //         function(MACHINE) {
 //             ...
 //         });

js-assembler/package.rkt

@@ -210,7 +210,7 @@ MACHINE.modules[~s] =
   (define (on-visit-src src ast stmts)
     (cond
      [(UninterpretedSource? src)
-      (fprintf op (UninterpretedSource-datum src))]
+      (fprintf op "~a" (UninterpretedSource-datum src))]
      [else
       (assemble/write-invoke stmts op)
       (fprintf op "(MACHINE, function() { ")]))

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

@@ -113,6 +113,11 @@
         'inspector');
 
 
+    var checkByte = makeCheckArgumentType(
+        plt.baselib.numbers.isByte,
+        'byte');
+
+
 
 
 
@@ -138,7 +143,7 @@
     exports.checkBox = checkBox;
     exports.checkMutableBox = checkMutableBox;
     exports.checkInspector = checkInspector;
-
+    exports.checkByte = checkByte;
 
 
 })(this['plt'].baselib);

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

@@ -156,44 +156,45 @@
 
 
     exceptions.IncompleteExn = IncompleteExn;
-    exceptions.incompleteExn = function(constructor, msg, args) { return new IncompleteExn(constructor, msg, args); };
+    exceptions.makeIncompleteExn = function(constructor, msg, args) { return new IncompleteExn(constructor, msg, args); };
     exceptions.isIncompleteExn = function(x) { return x instanceof IncompleteExn; };
 
 
     exceptions.Exn = Exn;
-    exceptions.exn = Exn.constructor;
+    exceptions.makeExn = Exn.constructor;
     exceptions.isExn = Exn.predicate;
     exceptions.exnMessage = function(exn) { return Exn.accessor(exn, 0); };
     exceptions.exnContMarks = function(exn) { return Exn.accessor(exn, 1); };
     exceptions.exnSetContMarks = function(exn, v) { Exn.mutator(exn, 1, v); };
 
     exceptions.ExnBreak = ExnBreak;
-    exceptions.exnBreak = ExnBreak.constructor;
+    exceptions.makeExnBreak = ExnBreak.constructor;
     exceptions.isExnBreak = ExnBreak.predicate;
     exceptions.exnBreakContinuation = 
         function(exn) { return ExnBreak.accessor(exn, 0); };
 
     exceptions.ExnFail = ExnFail;
-    exceptions.exnFail = ExnFail.constructor;
+    exceptions.makeExnFail = ExnFail.constructor;
     exceptions.isExnFail = ExnFail.predicate;
 
     exceptions.ExnFailContract = ExnFailContract;
-    exceptions.exnFailContract = ExnFailContract.constructor;
+    exceptions.makeExnFailContract = ExnFailContract.constructor;
     exceptions.isExnFailContract = ExnFailContract.predicate;
 
     exceptions.ExnFailContractArity = ExnFailContractArity;
-    exceptions.exnFailContractArity = ExnFailContractArity.constructor;
+    exceptions.makeExnFailContractArity = ExnFailContractArity.constructor;
     exceptions.isExnFailContractArity = ExnFailContractArity.predicate;
 
     exceptions.ExnFailContractVariable = ExnFailContractVariable;
-    exceptions.exnFailContractVariable = ExnFailContractVariable.constructor;
+    exceptions.makeExnFailContractVariable = ExnFailContractVariable.constructor;
     exceptions.isExnFailContractVariable = ExnFailContractVariable.predicate;
     exceptions.exnFailContractVariableId = 
         function(exn) { return ExnFailContractVariable.accessor(exn, 0); };
 
 
     exceptions.ExnFailContractDivisionByZero = ExnFailContractDivisionByZero;
-    exceptions.exnFailContractDivisionByZero = ExnFailContractDivisionByZero.constructor;
+    exceptions.makeExnFailContractDivisionByZero = 
+        ExnFailContractDivisionByZero.constructor;
     exceptions.isExnFailContractDivisionByZero = ExnFailContractDivisionByZero.predicate;
 
 

js-assembler/runtime-src/runtime.js

@@ -333,6 +333,18 @@ if(this['plt'] === undefined) { this['plt'] = {}; }
     };
 
 
+    var Pause = function(onPause) {
+        // onPause: MACHINE -> void
+        this.onPause = onPause || function(MACHINE) {};
+    };
+
+    var PAUSE = function(onPause) {
+        throw new Pause(onPause);
+    }
+    
+
+
+
     //////////////////////////////////////////////////////////////////////
     //////////////////////////////////////////////////////////////////////
     //////////////////////////////////////////////////////////////////////
@@ -361,15 +373,23 @@ if(this['plt'] === undefined) { this['plt'] = {}; }
                 // There are a few kinds of things that can get thrown
                 // during racket evaluation:
                 //
-                // functions: this gets thrown if the Racket code realizes
+                // functions: this gets thrown if the Racket code
-                // that the number of bounces has grown too large.  The thrown
+                // realizes that the number of bounces has grown too
-                // function represents a restarter function.
+                // large.  The thrown function represents a restarter
+                // function.  The running flag remains true.
                 //
-                // HaltError: causes evaluation to immediately halt.  We schedule
+                // Pause: causes the machine evaluation to pause, with
-                // the onHalt function of the HaltError to call afterwards.
+                // the expectation that it will restart momentarily.
+                // The running flag on the machine will remain true.
                 //
-                // everything else: otherwise, we send the exception value
+                // HaltError: causes evaluation to immediately halt.
+                // We schedule the onHalt function of the HaltError to
+                // call afterwards.  The running flag on the machine
+                // is set to false.
+                //
+                // Everything else: otherwise, we send the exception value
                 // to the current error handler and exit.
+                // The running flag is set to false.
 		if (typeof(e) === 'function') {
                     thunk = e;
                     MACHINE.callsBeforeTrampoline = STACK_LIMIT_ESTIMATE;
@@ -385,7 +405,19 @@ if(this['plt'] === undefined) { this['plt'] = {}; }
 		    } else {
                         continue;
                     }
-		} else if (e instanceof HaltError) {
+		} else if (e instanceof Pause) {
+                    var restart = function(thunk) {
+		        setTimeout(
+			    function() { trampoline(MACHINE, thunk); },
+			    0);
+                    };
+                    setTimeout(
+                        function() { 
+                            e.onPause(restart);
+                        },
+                        0);
+                    return;
+                } else if (e instanceof HaltError) {
 		    MACHINE.running = false;
                     setTimeout(
                         function() { e.onHalt(MACHINE); },
@@ -1922,6 +1954,7 @@ if(this['plt'] === undefined) { this['plt'] = {}; }
     exports['heir'] = heir;
     exports['makeClassPredicate'] = makeClassPredicate;
 
+    exports['PAUSE'] = PAUSE;
     exports['HaltError'] = HaltError;