Hook dataflow.js into Syndicate/js; add "during ... actor { ... }"

js/compiler/compiler.js

@@ -42,15 +42,14 @@ var forEachChild = (function () {
   return forEachChild;
 })();
 
-function buildActor(constructorES5, nameExpOpt, block) {
+function buildActor(nameExpOpt, block) {
   var nameExpStr;
   if (nameExpOpt.numChildren === 1) {
     nameExpStr = ', ' + nameExpOpt.asES5;
   } else {
     nameExpStr = '';
   }
-  return 'Syndicate.Actor.spawnActor(new '+constructorES5+', '+
+  return 'Syndicate.Actor.spawnActor(function() ' + block.asES5 + nameExpStr + ');';
-    'function() ' + block.asES5 + nameExpStr + ');';
 }
 
 function buildFacet(facetBlock, transitionBlock) {
@@ -58,11 +57,11 @@ function buildFacet(facetBlock, transitionBlock) {
     '\nSyndicate.Actor.createFacet()' +
     (facetBlock ? facetBlock.asES5 : '') +
     (transitionBlock ? transitionBlock.asES5 : '') +
-    '.completeBuild(); })();';
+    '.completeBuild(); }).call(this);';
 }
 
 function buildOnEvent(isTerminal, eventType, subscription, projection, bindings, body) {
-  return '\n.onEvent(' + isTerminal + ', ' + JSON.stringify(eventType) + ', ' +
+  return '\n.onEvent(Syndicate.Actor.PRIORITY_NORMAL, ' + isTerminal + ', ' + JSON.stringify(eventType) + ', ' +
     subscription + ', ' + projection +
     ', (function(' + bindings.join(', ') + ') ' + body + '))';
 }
@@ -86,11 +85,8 @@ function buildCaseEvent(eventPattern, body) {
 }
 
 var modifiedSourceActions = {
-  ActorStatement_noConstructor: function(_actor, _namedOpt, nameExpOpt, block) {
+  ActorStatement: function(_actor, _namedOpt, nameExpOpt, block) {
-    return buildActor('Object()', nameExpOpt, block);
+    return buildActor(nameExpOpt, block);
-  },
-  ActorStatement_withConstructor: function(_actor, ctorExp, _namedOpt, nameExpOpt, block) {
-    return buildActor(ctorExp.asES5, nameExpOpt, block);
   },
 
   DataspaceStatement_ground: function(_ground, _dataspace, maybeId, block) {
@@ -133,6 +129,22 @@ var modifiedSourceActions = {
       label + ', ' + JSON.stringify(formals) + ');';
   },
 
+  FieldDeclarationStatement: function(_field, memberExpr, _eq, initExpr, sc) {
+    return 'Syndicate.Actor.declareField(' + memberExpr.memberObjectExpr.asES5 + ', ' +
+      memberExpr.memberPropExpr.asES5 + ', ' + initExpr.asES5 + ')' +
+      sc.interval.contents;
+  },
+
+  MemberExpression_fieldRefExp: function (_field, memberExpr) {
+    return 'Syndicate.Actor.referenceField(' + memberExpr.memberObjectExpr.asES5 + ', ' +
+      memberExpr.memberPropExpr.asES5 + ')';
+  },
+
+  UnaryExpression_fieldDelExp: function (_delete, _field, memberExpr) {
+    return 'Syndicate.Actor.deleteField(' + memberExpr.memberObjectExpr.asES5 + ', ' +
+      memberExpr.memberPropExpr.asES5 + ')';
+  },
+
   SendMessageStatement: function(_colons, expr, sc) {
     return 'Syndicate.Dataspace.send(' + expr.asES5 + ')' + sc.interval.contents;
   },
@@ -165,6 +177,9 @@ var modifiedSourceActions = {
   FacetSituation_onEvent: function (_on, _event, id, block) {
     return '\n.addOnEventHandler((function(' + id.asES5 + ') ' + block.asES5 + '))';
   },
+  FacetSituation_dataflow: function (_dataflow, block) {
+    return '\n.addDataflow((function () ' + block.asES5 + '))';
+  },
   FacetSituation_during: function(_during, pattern, facetBlock) {
     var cachedAssertionVar = gensym('cachedAssertion');
     return buildOnEvent(false,
@@ -184,6 +199,28 @@ var modifiedSourceActions = {
                                      '{}') +
                         '.completeBuild(); }');
   },
+  FacetSituation_duringActor: function(_during, pattern, _actor, _named, nameExpOpt, facetBlock) {
+    var cachedAssertionVar = gensym('cachedAssertion');
+    var actorBlock = {
+      asES5: '{ ' + facetBlock.facetVarDecls +
+        '\nSyndicate.Actor.createFacet()' +
+        facetBlock.asES5 +
+        buildOnEvent(true,
+                     'retracted',
+                     pattern.instantiatedSubscription(cachedAssertionVar),
+                     pattern.instantiatedProjection(cachedAssertionVar),
+                     [],
+                     '{}') +
+        '.completeBuild(); }'
+    };
+    return buildOnEvent(false,
+                        'asserted',
+                        pattern.subscription,
+                        pattern.projection,
+                        pattern.bindings,
+                        '{ var '+cachedAssertionVar+' = '+pattern.instantiatedAssertion+';'+
+                        '\n' + buildActor(nameExpOpt, actorBlock) + ' }');
+  },
 
   AssertWhenClause: function(_when, _lparen, expr, _rparen) {
     return expr.asES5;
@@ -199,6 +236,24 @@ var modifiedSourceActions = {
 
 semantics.extendAttribute('modifiedSource', modifiedSourceActions);
 
+semantics.addAttribute('memberObjectExpr', {
+  MemberExpression_propRefExp: function(objExpr, _dot, id) {
+    return objExpr;
+  },
+  MemberExpression_arrayRefExp: function(objExpr, _lbrack, propExpr, _rbrack) {
+    return objExpr;
+  }
+});
+
+semantics.addAttribute('memberPropExpr', {
+  MemberExpression_propRefExp: function(objExpr, _dot, id) {
+    return { asES5: JSON.stringify(id.interval.contents) };
+  },
+  MemberExpression_arrayRefExp: function(objExpr, _lbrack, propExpr, _rbrack) {
+    return propExpr;
+  }
+});
+
 semantics.addAttribute('facetVarDecls', {
   FacetBlock: function (_leftParen, varDecls, _init, _situations, _done, _rightParen) {
     return varDecls.asES5.join(' ');
@@ -269,7 +324,7 @@ semantics.addAttribute('instantiatedAssertion', {
     var fragments = [];
     fragments.push('(function() { var _ = Syndicate.__; return ');
     children.forEach(function (c) { fragments.push(c.buildSubscription('instantiated')); });
-    fragments.push('; })()');
+    fragments.push('; }).call(this)');
     return fragments.join('');
   }
 });
@@ -345,6 +400,12 @@ semantics.addOperation('buildSubscription(mode)', {
     }
   },
 
+  MemberExpression_fieldRefExp: function (_field, memberExpr) {
+    return 'Syndicate.Actor.referenceField(' +
+      memberExpr.memberObjectExpr.buildSubscription(this.args.mode) + ', ' +
+      memberExpr.memberPropExpr.buildSubscription(this.args.mode) + ')';
+  },
+
   identifier: function(_name) {
     var i = this.interval.contents;
     if (i[0] === '$' && i.length > 1) {

js/compiler/demo-bankaccount.js

@@ -7,10 +7,13 @@ message type deposit(amount);
 
 ground dataspace {
   actor {
-    this.balance = 0;
+    field this.balance = 0;
 
     react {
       assert account(this.balance);
+      dataflow {
+        console.log("Balance inside account is", this.balance);
+      }
       on message deposit($amount) {
         this.balance += amount;
       }

js/compiler/demo-during-criterion-snapshotting.js

@@ -20,19 +20,19 @@ assertion type foo(x, y);
 
 ground dataspace {
   actor {
-    var x = 123;
+    field this.x = 123;
     react {
-      assert foo(x, 999);
+      assert foo(this.x, 999);
 
-      during foo(x, $v) {
+      during foo(this.x, $v) {
         do {
-          console.log('x=', x, 'v=', v);
+          console.log('x=', this.x, 'v=', v);
-          if (x === 123) {
+          if (this.x === 123) {
-            x = 124;
+            this.x = 124;
           }
         }
         finally {
-          console.log('finally for x=', x, 'v=', v);
+          console.log('finally for x=', this.x, 'v=', v);
         }
       }
     }

js/compiler/demo-filesystem.js

@@ -1,5 +1,17 @@
 // bin/syndicatec compiler/demo-filesystem.js | node
 
+// Good output:
+//
+// At least one reader exists for: hello.txt
+// hello.txt has content undefined
+// hello.txt has content "a"
+// hello.txt has content undefined
+// hello.txt has content "c"
+// hello.txt has content "quit demo"
+// The hello.txt file contained 'quit demo', so we will quit
+// second observer sees that hello.txt content is "final contents"
+// No remaining readers exist for: hello.txt
+
 var Syndicate = require('./src/main.js');
 
 assertion type file(name, content) = "file";
@@ -17,16 +29,16 @@ ground dataspace {
         do {
           console.log("At least one reader exists for:", name);
         }
-        assert file(name, this.files[name]);
+        assert file(name, field this.files[name]);
         finally {
           console.log("No remaining readers exist for:", name);
         }
       }
       on message saveFile($name, $newcontent) {
-        this.files[name] = newcontent;
+        field this.files[name] = newcontent;
       }
       on message deleteFile($name) {
-        delete this.files[name];
+        delete field this.files[name];
       }
     }
   }

js/compiler/syndicate.ohm

@@ -11,13 +11,13 @@ Syndicate <: ES5 {
     | DataspaceStatement
     | ActorFacetStatement
     | AssertionTypeDeclarationStatement
+    | FieldDeclarationStatement
     | SendMessageStatement
 
   FunctionBodyBlock = "{" FunctionBody "}"   // odd that this isn't in es5.ohm somewhere
 
   ActorStatement
-    = actor ~named CallExpression (named Expression<withIn>)? FunctionBodyBlock -- withConstructor
+    = actor (named Expression<withIn>)? FunctionBodyBlock
-    | actor (named Expression<withIn>)? FunctionBodyBlock                       -- noConstructor
 
   DataspaceStatement
     = ground dataspace identifier? FunctionBodyBlock -- ground
@@ -31,22 +31,33 @@ Syndicate <: ES5 {
   AssertionTypeDeclarationStatement
     = (assertion | message) type identifier "(" FormalParameterList ")" ("=" stringLiteral)? #(sc)
 
+  FieldDeclarationStatement = field MemberExpression "=" AssignmentExpression<withIn> #(sc)
+  MemberExpression += field MemberExpression -- fieldRefExp
+  UnaryExpression += delete field MemberExpression -- fieldDelExp
+
   SendMessageStatement = "::" Expression<withIn> #(sc)
 
   //---------------------------------------------------------------------------
   // Ongoing event handlers.
 
-  FacetBlock = "{" (VariableStatement | FunctionDeclaration)* FacetInitBlock? FacetSituation* FacetDoneBlock? "}"
+  FacetBlock = "{"
+    (VariableStatement | FieldDeclarationStatement | FunctionDeclaration)*
+    FacetInitBlock?
+    FacetSituation*
+    FacetDoneBlock?
+    "}"
   FacetStateTransitionBlock = "{" FacetStateTransition* "}"
 
   FacetInitBlock = do FunctionBodyBlock
   FacetDoneBlock = finally FunctionBodyBlock
 
   FacetSituation
-    = assert FacetPattern AssertWhenClause? #(sc) -- assert
+    = assert FacetPattern AssertWhenClause? #(sc)                      -- assert
-    | on FacetEventPattern FunctionBodyBlock      -- event
+    | on FacetEventPattern FunctionBodyBlock                           -- event
-    | on event identifier FunctionBodyBlock       -- onEvent
+    | on event identifier FunctionBodyBlock                            -- onEvent
-    | during FacetPattern FacetBlock              -- during
+    | dataflow FunctionBodyBlock                                       -- dataflow
+    | during FacetPattern FacetBlock                                   -- during
+    | during FacetPattern actor (named Expression<withIn>)? FacetBlock -- duringActor
 
   AssertWhenClause = when "(" Expression<withIn> ")"
 
@@ -76,9 +87,11 @@ Syndicate <: ES5 {
   assert = "assert" ~identifierPart
   asserted = "asserted" ~identifierPart
   assertion = "assertion" ~identifierPart
+  dataflow = "dataflow" ~identifierPart
   dataspace = "dataspace" ~identifierPart
   during = "during" ~identifierPart
   event = "event" ~identifierPart
+  field = "field" ~identifierPart
   ground = "ground" ~identifierPart
   message = "message" ~identifierPart
   metalevel = "metalevel" ~identifierPart

js/examples/button/.gitignore

@@ -0,0 +1 @@
+*.expanded.js

js/examples/button/Makefile

@@ -0,0 +1,7 @@
+all: index.expanded.js
+
+%.expanded.js: %.js
+	../../bin/syndicatec $< > $@ || (rm -f $@; false)
+
+clean:
+	rm -f *.expanded.js

js/examples/button/index.expanded.js

@@ -1,14 +0,0 @@
-"use strict";
-new Syndicate.Ground(function () {
-  Syndicate.UI.spawnUIDriver();
-
-  Syndicate.Actor.spawnActor(new Object(), function() {
-    var counter = 0;
-    var ui = new Syndicate.UI.Anchor();
-    Syndicate.Actor.createFacet()
-.addAssertion((function() { var _ = Syndicate.__; return Syndicate.Patch.assert(ui.html('#button-label',''+counter), 0); }))
-.onEvent(false, "message", (function() { var _ = Syndicate.__; return Syndicate.Patch.sub(Syndicate.UI.globalEvent('#counter','click',_), 0); }), (function() { var _ = Syndicate.__; return { assertion: Syndicate.UI.globalEvent('#counter','click',_), metalevel: 0 }; }), (function() {
-        counter++;
-      })).completeBuild();
-  });
-}).startStepping();

js/examples/button/index.js

@@ -2,12 +2,12 @@ ground dataspace {
   Syndicate.UI.spawnUIDriver();
 
   actor {
-    var counter = 0;
+    field this.counter = 0;
     var ui = new Syndicate.UI.Anchor();
     react {
-      assert ui.html('#button-label', '' + counter);
+      assert ui.html('#button-label', '' + this.counter);
       on message Syndicate.UI.globalEvent('#counter', 'click', _) {
-        counter++;
+        this.counter++;
       }
     }
   }

js/examples/chat/index.js

@@ -17,6 +17,8 @@ function spawnChatApp() {
 
   actor {
     var ui = new Syndicate.UI.Anchor();
+    field this.nym;
+    field this.status;
     react {
       on asserted inputValue('#nym',    $v) { this.nym = v; }
       on asserted inputValue('#status', $v) { this.status = v; }
@@ -83,17 +85,11 @@ assertion type inputValue(selector, value);
 function spawnInputChangeMonitor() {
   actor {
     react {
-      on asserted Syndicate.observe(inputValue($selector, _)) {
+      during Syndicate.observe(inputValue($selector, _)) actor {
-        actor {
+        field this.value = $(selector).val();
-          this.value = $(selector).val();
+        assert inputValue(selector, this.value);
-          react {
+        on message Syndicate.UI.globalEvent(selector, 'change', $e) {
-            assert inputValue(selector, this.value);
+          this.value = e.target.value;
-            on message Syndicate.UI.globalEvent(selector, 'change', $e) {
-              this.value = e.target.value;
-            }
-          } until {
-            case retracted Syndicate.observe(inputValue(selector, _));
-          }
         }
       }
     }

js/examples/iot/index.js

@@ -60,7 +60,7 @@ function spawnRemoteListener() {
 
 function spawnStoveSwitch() {
   actor {
-    this.powerOn = false;
+    field this.powerOn = false;
     this.ui = new Syndicate.UI.Anchor();
     react {
       assert componentPresent('stove switch');
@@ -85,7 +85,7 @@ function spawnStoveSwitch() {
 
 function spawnPowerDrawMonitor() {
   actor {
-    this.watts = 0;
+    field this.watts = 0;
     this.ui = new Syndicate.UI.Anchor();
     react {
       assert componentPresent('power draw monitor');

js/examples/location/index.js

@@ -40,7 +40,7 @@ ground dataspace G {
     var geocoder = new google.maps.Geocoder();
 
     var wsurl_base = 'wss://demo-broker.syndicate-lang.org:8443/location/';
-    var wsurl = wsurl_base + group_element.value.trim();
+    field this.wsurl = wsurl_base + group_element.value.trim();
 
     var watchId = ('geolocation' in navigator)
         && navigator.geolocation.watchPosition(Syndicate.Dataspace.wrap(function (pos) {
@@ -62,21 +62,21 @@ ground dataspace G {
         }));
 
     react {
-      var currentLocation = null;
+      field this.currentLocation = null;
       var selectedMarker = null;
 
-      assert brokerConnection(wsurl);
+      assert brokerConnection(this.wsurl);
-      assert toBroker(wsurl, currentLocation) when (currentLocation);
+      assert toBroker(this.wsurl, this.currentLocation) when (this.currentLocation);
 
       on message Syndicate.UI.globalEvent('#my_email', 'change', _) {
         var v = email_element.value.trim();
-        if (currentLocation) currentLocation[1] = v;
+        if (this.currentLocation) this.currentLocation = this.currentLocation.set(1, v);
         localStorage.my_email = v;
       }
 
       on message Syndicate.UI.globalEvent('#group', 'change', _) {
         localStorage.group = group_element.value.trim();
-        wsurl = wsurl_base + group_element.value.trim();
+        this.wsurl = wsurl_base + group_element.value.trim();
       }
 
       on message Syndicate.UI.globalEvent('#findMarker', 'click', $e) {
@@ -87,10 +87,10 @@ ground dataspace G {
       }
 
       on message ($loc = locationRecord(_, _, _, _, _)) {
-        currentLocation = loc;
+        this.currentLocation = loc;
       }
 
-      during fromBroker(wsurl, locationRecord($id, $email, _, _, _)) {
+      during fromBroker(this.wsurl, locationRecord($id, $email, _, _, _)) {
         var ui = new Syndicate.UI.Anchor();
         var marker = new google.maps.Marker({
           map: map,
@@ -131,7 +131,7 @@ ground dataspace G {
           selectMarker();
           if (latestPosition) map.panTo(latestPosition);
         }
-        on asserted fromBroker(wsurl, locationRecord(id, email, $timestamp, $lat, $lng)) {
+        on asserted fromBroker(this.wsurl, locationRecord(id, email, $timestamp, $lat, $lng)) {
           latestTimestamp = new Date(timestamp);
           latestPosition = {lat: lat, lng: lng};
           marker.setPosition(latestPosition);

js/examples/motion/index.js

@@ -14,8 +14,8 @@ ground dataspace G {
     var color = tinycolor('hsl ' + (Math.random() * 360 | 0) + ' 100% 50%').toHexString();
     var x = 0;
     var y = 0;
-    var publishedX = x;
+    field this.publishedX = x;
-    var publishedY = y;
+    field this.publishedY = y;
 
     function clamp(v) {
       var limit = 9.8;
@@ -28,10 +28,10 @@ ground dataspace G {
 
       assert Syndicate.UI.uiAttribute('rect#my_color', 'fill', color);
 
-      assert toBroker(wsurl, point(color, publishedX, publishedY));
+      assert toBroker(wsurl, point(color, this.publishedX, this.publishedY));
       on message Syndicate.Timer.periodicTick(100) {
-        publishedX = x;
+        this.publishedX = x;
-        publishedY = y;
+        this.publishedY = y;
       }
 
       on message Syndicate.UI.windowEvent('deviceorientation', $e) {

js/examples/smoketest-dsl/index.js

@@ -6,16 +6,16 @@ ground dataspace {
   actor {
     react until {
       case asserted Syndicate.observe(beep(_)) {
-        var counter = 0;
+        field this.counter = 0;
         react {
           do {
-            :: beep(counter++);
+            :: beep(this.counter++);
           }
           on message beep(_) {
-            :: beep(counter++);
+            :: beep(this.counter++);
           }
         } until {
-          case (counter >= 10);
+          case (this.counter > 10);
         }
       }
     }

js/examples/svg/index.js

@@ -4,6 +4,10 @@ ground dataspace G {
 
   actor {
     var ui = new Syndicate.UI.Anchor();
+    field this.angle;
+    field this.handX;
+    field this.handY;
+
     react {
       assert ui.html('#clock',
                      '<svg width="300px" viewBox="0 0 100 100">'+

js/examples/table/index.js

@@ -20,7 +20,7 @@ function spawnModel() {
 function spawnView() {
   actor named 'view' {
     var ui = new Syndicate.UI.Anchor();
-    var orderColumn = 2;
+    field this.orderColumn = 2;
 
     function cell(text) {
       // Should escape text in a real application.
@@ -28,13 +28,13 @@ function spawnView() {
     }
 
     react {
-      on message setSortColumn($c) { orderColumn = c; }
+      on message setSortColumn($c) { this.orderColumn = c; }
 
       during person($id, $firstName, $lastName, $address, $age) {
         assert ui.context(id)
           .html('table#the-table tbody',
                 '<tr>' + [id, firstName, lastName, address, age].map(cell).join('') + '</tr>',
-                [id, firstName, lastName, address, age][orderColumn]);
+                [id, firstName, lastName, address, age][this.orderColumn]);
       }
     }
   }

js/examples/textfield-dsl/index.js

@@ -26,24 +26,24 @@ function piece(text, pos, lo, hi, cls) {
 
 function spawnGui() {
   actor {
-    this.text = '';
-    this.pos = 0;
-    this.highlightState = false;
-
-    this.updateDisplay = function () {
-      var text = this.text;
-      var pos = this.pos;
-      var highlight = this.highlightState;
-      var hLeft = highlight ? highlight[0] : 0;
-      var hRight = highlight ? highlight[1] : 0;
-      document.getElementById("fieldContents").innerHTML = highlight
-	? piece(text, pos, 0, hLeft, "normal") +
-	piece(text, pos, hLeft, hRight, "highlight") +
-	piece(text, pos, hRight, text.length + 1, "normal")
-	: piece(text, pos, 0, text.length + 1, "normal");
-    };
-
     react {
+      field this.text = '';
+      field this.pos = 0;
+      field this.highlightState = false;
+
+      dataflow {
+        var text = this.text;
+        var pos = this.pos;
+        var highlight = this.highlightState;
+        var hLeft = highlight ? highlight[0] : 0;
+        var hRight = highlight ? highlight[1] : 0;
+        document.getElementById("fieldContents").innerHTML = highlight
+	  ? piece(text, pos, 0, hLeft, "normal") +
+	  piece(text, pos, hLeft, hRight, "highlight") +
+	  piece(text, pos, hRight, text.length + 1, "normal")
+	  : piece(text, pos, 0, text.length + 1, "normal");
+      }
+
       on message globalEvent("#inputRow", "+keydown", $event) {
         switch (event.keyCode) {
           case 37 /* left  */: :: fieldCommand("cursorLeft"); break;
@@ -67,12 +67,10 @@ function spawnGui() {
       on asserted fieldContents($text, $pos) {
         this.text = text;
         this.pos = pos;
-        this.updateDisplay();
       }
 
       on asserted highlight($state) {
         this.highlightState = state;
-        this.updateDisplay();
       }
     }
   }
@@ -83,10 +81,10 @@ function spawnGui() {
 
 function spawnModel() {
   actor {
-    this.fieldValue = "initial";
-    this.cursorPos = this.fieldValue.length; /* positions address gaps between characters */
-
     react {
+      field this.fieldValue = "initial";
+      field this.cursorPos = this.fieldValue.length; /* positions address gaps between characters */
+
       assert fieldContents(this.fieldValue, this.cursorPos);
 
       on message fieldCommand("cursorLeft") {
@@ -126,29 +124,28 @@ function spawnModel() {
 
 function spawnSearch() {
   actor {
-    this.fieldValue = "";
-    this.highlight = false;
-
-    this.search = function () {
-      var searchtext = document.getElementById("searchBox").value;
-      if (searchtext) {
-	var pos = this.fieldValue.indexOf(searchtext);
-	this.highlight = (pos !== -1) && [pos, pos + searchtext.length];
-      } else {
-	this.highlight = false;
-      }
-    };
-
     react {
+      field this.searchtext = document.getElementById("searchBox").value;
+      field this.fieldValue = "";
+      field this.highlight = false;
+
       assert highlight(this.highlight);
 
+      dataflow {
+        if (this.searchtext) {
+	  var pos = this.fieldValue.indexOf(this.searchtext);
+	  this.highlight = (pos !== -1) && [pos, pos + this.searchtext.length];
+        } else {
+	  this.highlight = false;
+        }
+      }
+
       on message globalEvent("#searchBox", "input", $event) {
-        this.search();
+        this.searchtext = document.getElementById("searchBox").value;
       }
 
       on asserted fieldContents($text, _) {
         this.fieldValue = text;
-        this.search();
       }
     }
   }

js/examples/todo/index.js

@@ -25,11 +25,11 @@ assertion type show(completed);
 
 function todoListItemModel(initialId, initialTitle, initialCompleted) {
   actor {
-    this.id = initialId;
-    this.title = initialTitle;
-    this.completed = initialCompleted;
-
     react {
+      field this.id = initialId;
+      field this.title = initialTitle;
+      field this.completed = initialCompleted;
+
       assert todo(this.id, this.title, this.completed);
 
       on message setCompleted(this.id, $v) { this.completed = v; }
@@ -58,8 +58,9 @@ function getTemplate(id) {
 function todoListItemView(id) {
   actor {
     this.ui = new Syndicate.UI.Anchor();
-    this.editing = false;
     react {
+      field this.editing = false;
+
       during todo(id, $title, $completed) {
         during show(completed) {
           assert this.ui.html('.todo-list',
@@ -158,15 +159,15 @@ ground dataspace G {
   }
 
   actor {
-    var completedCount = 0;
-    var activeCount = 0;
     react {
-      on asserted  todo($id, _, $completed) { if (completed) completedCount++; else activeCount++; }
+      field this.completedCount = 0;
-      on retracted todo($id, _, $completed) { if (completed) completedCount--; else activeCount--; }
+      field this.activeCount = 0;
-      assert activeTodoCount(activeCount);
+      on asserted  todo($id, _, $c) { if (c) this.completedCount++; else this.activeCount++; }
-      assert completedTodoCount(completedCount);
+      on retracted todo($id, _, $c) { if (c) this.completedCount--; else this.activeCount--; }
-      assert totalTodoCount(activeCount + completedCount);
+      assert activeTodoCount(this.activeCount);
-      assert allCompleted() when (completedCount > 0 && activeCount === 0);
+      assert completedTodoCount(this.completedCount);
+      assert totalTodoCount(this.activeCount + this.completedCount);
+      assert allCompleted() when (this.completedCount > 0 && this.activeCount === 0);
     }
   }
 

js/examples/two-buyer-protocol/index.js

@@ -91,19 +91,27 @@ function seller() {
 /// We give our actor two state variables: a dictionary recording our
 /// inventory of books (mapping title to price), and a counter
 /// tracking the next order ID to be allocated.
+///
+/// We mark each property (entry) in the `books` table as a *field* so
+/// that dependency-tracking on a per-book basis is enabled. As a result,
+/// when a book is sold, any client still interested in its price will
+/// learn that the book is no longer available.
+///
+/// We do not enable dependency-tracking for either the `books` table
+/// itself or the `nextOrderId` field: nothing depends on tracking
+/// changes in their values.
 
-    this.books = {
+    this.books = {};
-      "The Wind in the Willows": 3.95,
+    field this.books["The Wind in the Willows"] = 3.95;
-      "Catch 22": 2.22,
+    field this.books["Catch 22"] = 2.22;
-      "Candide": 34.95
+    field this.books["Candide"] = 34.95;
-    };
     this.nextOrderId = 10001483;
 
 /// Looking up a price yields `false` if no such book is in our
 /// inventory.
 
     this.priceOf = function (title) {
-      return (title in this.books) && this.books[title];
+      return (title in this.books) && field this.books[title];
     };
 
 /// The seller responds to interest in bookQuotes by asserting a
@@ -134,7 +142,7 @@ function seller() {
 /// replying to the orderer.
 
           var orderId = this.nextOrderId++;
-          delete this.books[title];
+          delete field this.books[title];
 
           actor {
             whileRelevantAssert(

js/src/actor.js

@@ -8,20 +8,22 @@ var Mux = require('./mux.js');
 var Patch = require('./patch.js');
 var Trie = require('./trie.js');
 var Util = require('./util.js');
+var Dataflow = require('./dataflow.js');
 
 //---------------------------------------------------------------------------
 
-function spawnActor(state, bootFn, optName) {
+function spawnActor(bootFn, optName) {
-  Dataspace.spawn(new Actor(state, bootFn, optName));
+  Dataspace.spawn(new Actor(bootFn, optName));
 }
 
-function Actor(state, bootFn, optName) {
+function Actor(bootFn, optName) {
-  this.state = state;
+  this.fields = {};
   this.facets = Immutable.Set();
   this.mux = new Mux.Mux();
   this.previousKnowledge = Trie.emptyTrie;
   this.knowledge = Trie.emptyTrie;
   this.pendingActions = [];
+  this.dataflowGraph = new Dataflow.Graph();
 
   if (typeof optName !== 'undefined') {
     this.name = optName;
@@ -29,36 +31,82 @@ function Actor(state, bootFn, optName) {
 
   this.boot = function() {
     var self = this;
-    withCurrentFacet(null, function () {
+    withCurrentFacet(self, null, function () {
-      bootFn.call(self.state);
+      bootFn.call(self.fields);
     });
-    self.checkForTermination();
+    this.quiesce();
   };
 }
 
+Actor.current = null;
+
+(function () {
+  var priorities = ['PRIORITY_QUERY_HIGH',
+                    'PRIORITY_QUERY',
+                    'PRIORITY_QUERY_HANDLER',
+                    'PRIORITY_NORMAL'];
+  for (var i = 0; i < priorities.length; i++) {
+    Actor[priorities[i]] = i;
+  }
+})();
+
+Actor.prototype.nextPendingAction = function (probe) {
+  for (var i = 0; i < this.pendingActions.length; i++) {
+    var q = this.pendingActions[i];
+    if (q.length > 0) {
+      return probe ? true : q.shift();
+    }
+  }
+  return false;
+};
+
 Actor.prototype.handleEvent = function(e) {
+  var actor = this;
   if (e.type === 'stateChange') {
     this.previousKnowledge = this.knowledge;
     this.knowledge = e.patch.updateInterests(this.knowledge);
   }
-  if (this.pendingActions.length > 0) {
+  if (this.nextPendingAction(true)) {
     throw new Error('Syndicate: pendingActions must not be nonempty at start of handleEvent');
   }
   this.facets.forEach(function (f) {
-    withCurrentFacet(f, function () { f.handleEvent(e); });
+    withCurrentFacet(actor, f, function () { f.handleEvent(e); });
   });
-  while (this.pendingActions.length) {
+  this.quiesce();
-    var entry = this.pendingActions.shift();
+};
-    withCurrentFacet(entry.facet, entry.action);
+
+Actor.prototype.quiesce = function() {
+  var actor = this;
+
+  while (true) {
+    var entry = this.nextPendingAction(false);
+    if (!entry) break;
+
+    withCurrentFacet(actor, entry.facet, entry.action);
+
+    this.dataflowGraph.repairDamage(function (subjectId) {
+      var facet = subjectId[0];
+      var endpoint = subjectId[1];
+      withCurrentFacet(actor, facet, function () {
+        // TODO: coalesce patches within a single actor
+        var aggregate = Patch.emptyPatch;
+        var patch = Patch.retract(__).andThen(endpoint.subscriptionFn.call(facet.fields));
+        var r = facet.actor.mux.updateStream(endpoint.eid, patch);
+        aggregate = aggregate.andThen(r.deltaAggregate);
+        Dataspace.stateChange(aggregate);
+      });
+    });
   }
-  this.facets.forEach(function (f) {
+
-    withCurrentFacet(f, function () { f.refresh(); });
-  });
   this.checkForTermination();
 };
 
-Actor.prototype.pushAction = function (a) {
+Actor.prototype.pushAction = function (a, priorityOpt) {
-  this.pendingActions.push({facet: Facet.current, action: a});
+  var priority = typeof priorityOpt === 'undefined' ? Actor.PRIORITY_NORMAL : priorityOpt;
+  while (this.pendingActions.length < priority + 1) {
+    this.pendingActions.push([]);
+  }
+  this.pendingActions[priority].push({facet: Facet.current, action: a});
 };
 
 Actor.prototype.addFacet = function(facet) {
@@ -88,29 +136,34 @@ function Facet(actor) {
   this.doneBlocks = Immutable.List();
   this.children = Immutable.Set();
   this.parent = Facet.current;
+  this.fields = Dataflow.Graph.newScope((this.parent && this.parent.fields) || actor.fields);
   this.terminated = false;
 }
 
 Facet.current = null;
 
-function withCurrentFacet(facet, f) {
+function withCurrentFacet(actor, facet, f) {
-  var previous = Facet.current;
+  var previousActor = Actor.current;
+  var previousFacet = Facet.current;
+  Actor.current = actor;
   Facet.current = facet;
   var result;
   try {
     result = f();
   } catch (e) {
-    Facet.current = previous;
+    Actor.current = previousActor;
+    Facet.current = previousFacet;
     throw e;
   }
-  Facet.current = previous;
+  Actor.current = previousActor;
+  Facet.current = previousFacet;
   return result;
 }
 
 Facet.prototype.handleEvent = function(e) {
   var facet = this;
   facet.endpoints.forEach(function(endpoint) {
-    endpoint.handlerFn.call(facet.actor.state, e);
+    endpoint.handlerFn.call(facet.fields, e);
   });
 };
 
@@ -118,27 +171,47 @@ Facet.prototype.addAssertion = function(assertionFn) {
   return this.addEndpoint(new Endpoint(assertionFn, function(e) {}));
 };
 
-Facet.prototype.addOnEventHandler = function(handler) {
+Facet.prototype.addOnEventHandler = function(handler, priorityOpt) {
   var facet = this;
   return this.addEndpoint(new Endpoint(function () { return Patch.emptyPatch; }, function (e) {
-    facet.actor.pushAction(function () { handler(e); });
+    facet.actor.pushAction(function () { handler(e); }, priorityOpt);
   }));
 };
 
-Facet.prototype.onEvent = function(isTerminal, eventType, subscriptionFn, projectionFn, handlerFn) {
+Facet.prototype.addDataflow = function(subjectFunction) {
+  var facet = this;
+  return this.addEndpoint(new Endpoint(function () {
+    var subjectId = facet.actor.dataflowGraph.currentSubjectId;
+    facet.actor.pushAction(function () {
+      facet.actor.dataflowGraph.withSubject(subjectId, function () {
+        subjectFunction.call(facet.fields);
+      });
+    });
+    return Patch.emptyPatch;
+  }, function (e) {}));
+};
+
+Facet.prototype.onEvent = function(priority,
+                                   isTerminal,
+                                   eventType,
+                                   subscriptionFn,
+                                   projectionFn,
+                                   handlerFn)
+{
   var facet = this;
   switch (eventType) {
 
   case 'message':
     return this.addEndpoint(new Endpoint(subscriptionFn, function(e) {
       if (e.type === 'message') {
-        var proj = projectionFn.call(facet.actor.state);
+        var proj = projectionFn.call(facet.fields);
         var spec = Patch.prependAtMeta(proj.assertion, proj.metalevel);
         var match = Trie.matchPattern(e.message, spec);
         // console.log(match);
         if (match) {
           if (isTerminal) { facet.terminate(); }
-          facet.actor.pushAction(function () { Util.kwApply(handlerFn, facet.actor.state, match); });
+          facet.actor.pushAction(function () { Util.kwApply(handlerFn, facet.fields, match); },
+                                 priority);
         }
       }
     }));
@@ -147,7 +220,7 @@ Facet.prototype.onEvent = function(isTerminal, eventType, subscriptionFn, projec
   case 'retracted':
     return this.addEndpoint(new Endpoint(subscriptionFn, function(e) {
       if (e.type === 'stateChange') {
-        var proj = projectionFn.call(facet.actor.state);
+        var proj = projectionFn.call(facet.fields);
         var spec = Patch.prependAtMeta(proj.assertion, proj.metalevel);
         var objects = Trie.projectObjects(eventType === 'asserted'
                                           ? e.patch.added
@@ -163,8 +236,8 @@ Facet.prototype.onEvent = function(isTerminal, eventType, subscriptionFn, projec
                 facet.terminate();
               }
               facet.actor.pushAction(function () {
-                Util.kwApply(handlerFn, facet.actor.state, o);
+                Util.kwApply(handlerFn, facet.fields, o);
-              });
+              }, priority);
             }
           });
         }
@@ -172,17 +245,17 @@ Facet.prototype.onEvent = function(isTerminal, eventType, subscriptionFn, projec
     }));
 
   case 'risingEdge':
-    var endpoint = new Endpoint(function() { return Patch.emptyPatch; },
+    var endpoint = new Endpoint(function() {
-                                function(e) {
+      var newValue = subscriptionFn.call(facet.fields);
-                                  var newValue = subscriptionFn.call(facet.actor.state);
+      if (newValue && !this.currentValue) {
-                                  if (newValue && !this.currentValue) {
+        if (isTerminal) { facet.terminate(); }
-                                    if (isTerminal) { facet.terminate(); }
+        facet.actor.pushAction(function () {
-                                    facet.actor.pushAction(function () {
+          handlerFn.call(facet.fields);
-                                      handlerFn.call(facet.actor.state);
+        }, priority);
-                                    });
+      }
-                                  }
+      this.currentValue = newValue;
-                                  this.currentValue = newValue;
+      return Patch.emptyPatch;
-                                });
+    }, function(e) {});
     endpoint.currentValue = false;
     return this.addEndpoint(endpoint);
 
@@ -206,11 +279,15 @@ Facet.prototype.interestWas = function(assertedOrRetracted, pat) {
 };
 
 Facet.prototype.addEndpoint = function(endpoint) {
-  var patch = endpoint.subscriptionFn.call(this.actor.state);
+  var facet = this;
-  var r = this.actor.mux.addStream(patch);
+  var patch = facet.actor.dataflowGraph.withSubject([facet, endpoint], function () {
-  this.endpoints = this.endpoints.set(r.pid, endpoint);
+    return endpoint.subscriptionFn.call(facet.fields);
+  });
+  var r = facet.actor.mux.addStream(patch);
+  endpoint.eid = r.pid;
+  facet.endpoints = facet.endpoints.set(endpoint.eid, endpoint);
   Dataspace.stateChange(r.deltaAggregate);
-  return this; // for chaining
+  return facet; // for chaining
 };
 
 Facet.prototype.addInitBlock = function(thunk) {
@@ -223,28 +300,17 @@ Facet.prototype.addDoneBlock = function(thunk) {
   return this;
 };
 
-Facet.prototype.refresh = function() {
-  var facet = this;
-  var aggregate = Patch.emptyPatch;
-  this.endpoints.forEach(function(endpoint, eid) {
-    var patch = Patch.retract(__).andThen(endpoint.subscriptionFn.call(facet.actor.state));
-    var r = facet.actor.mux.updateStream(eid, patch);
-    aggregate = aggregate.andThen(r.deltaAggregate);
-  });
-  Dataspace.stateChange(aggregate);
-};
-
 Facet.prototype.completeBuild = function() {
   var facet = this;
   this.actor.addFacet(this);
   if (this.parent) {
     this.parent.children = this.parent.children.add(this);
   }
-  withCurrentFacet(facet, function () {
+  withCurrentFacet(this.actor, facet, function () {
-    facet.initBlocks.forEach(function(b) { b.call(facet.actor.state); });
+    facet.initBlocks.forEach(function(b) { b.call(facet.fields); });
   });
   var initialEvent = _Dataspace.stateChange(new Patch.Patch(facet.actor.knowledge, Trie.emptyTrie));
-  withCurrentFacet(facet, function () { facet.handleEvent(initialEvent); });
+  withCurrentFacet(this.actor, facet, function () { facet.handleEvent(initialEvent); });
 };
 
 Facet.prototype.terminate = function() {
@@ -267,13 +333,13 @@ Facet.prototype.terminate = function() {
 
   this.actor.removeFacet(this);
 
-  withCurrentFacet(facet, function () {
-    facet.doneBlocks.forEach(function(b) { b.call(facet.actor.state); });
-  });
-
   this.children.forEach(function (child) {
     child.terminate();
   });
+
+  withCurrentFacet(this.actor, facet, function () {
+    facet.doneBlocks.forEach(function(b) { b.call(facet.fields); });
+  });
 };
 
 //---------------------------------------------------------------------------
@@ -281,9 +347,37 @@ Facet.prototype.terminate = function() {
 function Endpoint(subscriptionFn, handlerFn) {
   this.subscriptionFn = subscriptionFn;
   this.handlerFn = handlerFn;
+  this.eid = 'uninitialized_eid'; // initialized later
+}
+
+//---------------------------------------------------------------------------
+
+function referenceField(obj, prop) {
+  if (!(prop in obj)) {
+    Actor.current.dataflowGraph.recordObservation(Immutable.List.of(obj, prop));
+  }
+  return obj[prop];
+}
+
+function declareField(obj, prop, init) {
+  if (prop in obj) {
+    obj[prop] = init;
+  } else {
+    Actor.current.dataflowGraph.defineObservableProperty(obj, prop, init, {
+      objectId: Immutable.List.of(obj, prop)
+    });
+  }
+}
+
+function deleteField(obj, prop) {
+  Actor.current.dataflowGraph.recordDamage(Immutable.List.of(obj, prop));
+  return delete obj[prop];
 }
 
 //---------------------------------------------------------------------------
 
 module.exports.spawnActor = spawnActor;
 module.exports.createFacet = createFacet;
+module.exports.referenceField = referenceField;
+module.exports.declareField = declareField;
+module.exports.deleteField = deleteField;

js/src/dataflow.js

@@ -9,7 +9,6 @@ function Graph() {
   this.edgesReverse = Immutable.Map();
   this.damagedNodes = Immutable.Set();
   this.currentSubjectId = null;
-  this.enforceSubjectPresence = true;
 }
 
 Graph.prototype.withSubject = function (subjectId, f) {
@@ -30,8 +29,6 @@ Graph.prototype.recordObservation = function (objectId) {
   if (this.currentSubjectId) {
     this.edgesForward = MapSet.add(this.edgesForward, objectId, this.currentSubjectId);
     this.edgesReverse = MapSet.add(this.edgesReverse, this.currentSubjectId, objectId);
-  } else if (this.enforceSubjectPresence) {
-    throw new Error('Attempt to observe ' + objectId + ' with no currentSubjectId');
   }
 };
 
@@ -80,7 +77,7 @@ Graph.prototype.repairDamage = function (repairNode) {
 Graph.prototype.defineObservableProperty = function (obj, prop, value, maybeOptions) {
   var graph = this;
   var options = typeof maybeOptions === 'undefined' ? {} : maybeOptions;
-  var objectId = '__' + (options.baseId || prop);
+  var objectId = options.objectId || '__' + prop;
   Object.defineProperty(obj, prop, {
     configurable: true,
     enumerable: true,

js/src/main.js

@@ -33,6 +33,7 @@ module.exports.Reflect = require("./reflect.js");
 module.exports.WakeDetector = require("./wake-detector-driver.js");
 module.exports.Codec = require("./codec.js");
 module.exports.Broker = require("./broker.js");
+module.exports.Dataflow = require("./dataflow.js");
 
 module.exports.Patch = require("./patch.js");
 copyKeys(['emptyPatch',

js/src/struct.js

@@ -54,6 +54,19 @@ function Structure(meta, fields) {
   }
 }
 
+Structure.prototype.clone = function () {
+  return new Structure(this.meta, this.fields);
+};
+
+Structure.prototype.get = function (index) {
+  return this[index];
+};
+
+Structure.prototype.set = function (index, value) {
+  var s = this.clone();
+  s[index] = s.fields[index] = value;
+};
+
 function reviveStructs(j) {
   if (Array.isArray(j)) {
     return j.map(reviveStructs);

js/test/test-dataflow.js

@@ -7,7 +7,7 @@ var Dataflow = require('../src/dataflow.js');
 
 function Cell(graph, initialValue, name) {
   this.objectId = graph.defineObservableProperty(this, 'value', initialValue, {
-    baseId: name,
+    objectId: name,
     noopGuard: function (a, b) {
       return a === b;
     }
@@ -50,7 +50,6 @@ describe('dataflow edges, damage and subjects', function () {
 describe('DerivedCell', function () {
   describe('simple case', function () {
     var g = new Dataflow.Graph();
-    g.enforceSubjectPresence = false;
     var c = DerivedCell(g, 'c', function () { return 123; });
     var d = DerivedCell(g, 'd', function () { return c.value * 2; });
     it('should be properly initialized', function () {
@@ -79,7 +78,6 @@ describe('DerivedCell', function () {
 
   describe('a more complex case', function () {
     var g = new Dataflow.Graph();
-    g.enforceSubjectPresence = false;
 
     function add(a, b) { return a + b; }
     var xs = new Cell(g, Immutable.List.of(1, 2, 3, 4), 'xs');
@@ -132,7 +130,6 @@ describe('DerivedCell', function () {
 
 describe('scopes', function () {
   var g = new Dataflow.Graph();
-  g.enforceSubjectPresence = false;
 
   function buildScopes() {
     var rootScope = {};
@@ -147,6 +144,9 @@ describe('scopes', function () {
     expect(ss.root.p).to.be(123);
     expect(ss.mid.p).to.be(123);
     expect(ss.outer.p).to.be(123);
+    expect('p' in ss.root).to.be(true);
+    expect('p' in ss.mid).to.be(true);
+    expect('p' in ss.outer).to.be(true);
   });
 
   it('should make changes at root visible at leaves', function () {
@@ -173,6 +173,9 @@ describe('scopes', function () {
     expect(ss.outer.p).to.be(123);
     expect(ss.mid.p).to.be(undefined);
     expect(ss.root.p).to.be(undefined);
+    expect('p' in ss.root).to.be(false);
+    expect('p' in ss.mid).to.be(false);
+    expect('p' in ss.outer).to.be(true);
   });
 
   it('should hide middle definitions from roots but show to leaves', function () {
@@ -181,5 +184,8 @@ describe('scopes', function () {
     expect(ss.outer.p).to.be(123);
     expect(ss.mid.p).to.be(123);
     expect(ss.root.p).to.be(undefined);
+    expect('p' in ss.root).to.be(false);
+    expect('p' in ss.mid).to.be(true);
+    expect('p' in ss.outer).to.be(true);
   });
 });