[WIP] Editor

lib/builder.dart

@@ -237,6 +237,7 @@ class BuiltinStub {
     'SchemeSymbol': 'symbol',
     'Procedure': 'procedure',
     'Pair': 'pair',
+    'SchemeList': 'list',
     'SchemeEventListener': 'event listener',
     'JsValue': 'js object',
     'JsProcedure': 'js function',

lib/src/core/interpreter.dart

@@ -34,6 +34,18 @@ class Interpreter {
     StandardLibrary().importAll(globalEnv);
   }
 
+  /// Creates a clone of this interpreter, with a copy of this interpreter's
+  /// current global environment and settings, but a reset logger, exit
+  /// listener, and frame counter.
+  Interpreter clone() {
+    var cloned = Interpreter(impl);
+    cloned.language = language;
+    cloned.tailCallOptimized = tailCallOptimized;
+    cloned.globalEnv.bindings.addAll(globalEnv.bindings);
+    cloned.globalEnv.hidden.addAll(globalEnv.hidden);
+    return cloned;
+  }
+
   @deprecated
   ProjectInterface get implementation => impl;
 

lib/src/core/standard_library.dart

@@ -244,13 +244,13 @@ class StandardLibrary extends SchemeLibrary with _$StandardLibraryMixin {
   bool isZero(Number x) => x == Number.zero;
 
   /// Forces [promise], evaluating it if necessary.
-  Expression force(Promise promise) => promise.force();
+  Value force(Promise promise) => promise.force();
 
   /// Finds the rest of [stream].
   ///
   /// Equivalent to (force (cdr [stream]))
   @SchemeSymbol("cdr-stream")
-  Expression cdrStream(Pair stream) => force(cdr(stream));
+  Value cdrStream(Pair stream) => force(cdr(stream));
 
   /// Mutates the car of [pair] to be [val].
   @SchemeSymbol("set-car!")

lib/src/core/standard_library.g.dart

@@ -53,8 +53,8 @@ abstract class _$StandardLibraryMixin {
   bool isEven(Number x);
   bool isOdd(Number x);
   bool isZero(Number x);
-  Expression force(Promise promise);
-  Expression cdrStream(Pair stream);
+  Value force(Promise promise);
+  Value cdrStream(Pair stream);
   void setCar(Pair pair, Value val);
   void setCdr(Pair pair, Value val, Frame env);
   String getRuntimeType(Expression expression);
@@ -65,7 +65,7 @@ abstract class _$StandardLibraryMixin {
       return this.apply(__exprs[0], SchemeList(__exprs[1]), __env);
     }, 2,
         docs: Docs("apply", "Applies [procedure] to the given [args]\n",
-            [Param("procedure", "procedure"), Param(null, "args")],
+            [Param("procedure", "procedure"), Param("list", "args")],
             returnType: "value"));
     addBuiltin(__env, const SchemeSymbol("display"), (__exprs, __env) {
       this.display(__exprs[0], __env);
@@ -220,7 +220,8 @@ abstract class _$StandardLibraryMixin {
     }, 0,
         maxArgs: -1,
         docs: Docs.variable(
-            "list", "Constructs a list from zero or more arguments.\n"));
+            "list", "Constructs a list from zero or more arguments.\n",
+            returnType: "list"));
     addBuiltin(__env, const SchemeSymbol("map"), (__exprs, __env) {
       if (__exprs[0] is! Procedure || __exprs[1] is! PairOrEmpty)
         throw SchemeException('Argument of invalid type passed to map.');
@@ -229,7 +230,8 @@ abstract class _$StandardLibraryMixin {
         docs: Docs(
             "map",
             "Constructs a new list from calling [fn] on each item in [lst].\n",
-            [Param("procedure", "fn"), Param(null, "lst")]));
+            [Param("procedure", "fn"), Param("list", "lst")],
+            returnType: "list"));
     addBuiltin(__env, const SchemeSymbol("filter"), (__exprs, __env) {
       if (__exprs[0] is! Procedure || __exprs[1] is! PairOrEmpty)
         throw SchemeException('Argument of invalid type passed to filter.');
@@ -238,7 +240,8 @@ abstract class _$StandardLibraryMixin {
         docs: Docs(
             "filter",
             "Constructs a new list of all items in [lst] that return true when passed\nto [pred].\n",
-            [Param("procedure", "pred"), Param(null, "lst")]));
+            [Param("procedure", "pred"), Param("list", "lst")],
+            returnType: "list"));
     addBuiltin(__env, const SchemeSymbol("reduce"), (__exprs, __env) {
       if (__exprs[0] is! Procedure || __exprs[1] is! PairOrEmpty)
         throw SchemeException('Argument of invalid type passed to reduce.');
@@ -247,7 +250,7 @@ abstract class _$StandardLibraryMixin {
         docs: Docs(
             "reduce",
             "Reduces [lst] into a single expression by combining items with [combiner].\n",
-            [Param("procedure", "combiner"), Param(null, "lst")],
+            [Param("procedure", "combiner"), Param("list", "lst")],
             returnType: "value"));
     addVariableBuiltin(__env, const SchemeSymbol("+"), (__exprs, __env) {
       if (__exprs.any((x) => x is! Number))
@@ -421,7 +424,7 @@ abstract class _$StandardLibraryMixin {
     }, 1,
         docs: Docs("force", "Forces [promise], evaluating it if necessary.\n",
             [Param(null, "promise")],
-            returnType: "expression"));
+            returnType: "value"));
     addBuiltin(__env, const SchemeSymbol("cdr-stream"), (__exprs, __env) {
       if (__exprs[0] is! Pair)
         throw SchemeException('Argument of invalid type passed to cdr-stream.');
@@ -431,7 +434,7 @@ abstract class _$StandardLibraryMixin {
             "cdr-stream",
             "Finds the rest of [stream].\n\nEquivalent to (force (cdr [stream]))\n",
             [Param("pair", "stream")],
-            returnType: "expression"));
+            returnType: "value"));
     addBuiltin(__env, const SchemeSymbol("set-car!"), (__exprs, __env) {
       if (__exprs[0] is! Pair)
         throw SchemeException('Argument of invalid type passed to set-car!.');

lib/src/core/values.dart

@@ -99,19 +99,19 @@ class Thunk extends Value {
 /// whose cdr is a promise that evaluates to another stream or the empty list.
 ///
 /// It is semantically different from a JS Promise, which is equivalent to a
-/// Dart [Future]. The Scheme equivalent of [Future] is [AsyncExpression].
+/// Dart [Future]. The Scheme equivalent of [Future] is [AsyncValue].
 ///
 /// A Scheme stream is semantically different from a Dart Stream, which is an
 /// asynchronous sequence. A Scheme stream is analogous to a lazily-computed
 /// iterable built on a linked list.
 class Promise extends Value {
-  Expression expr;
+  Value expr;
   final Frame env;
   bool _evaluated = false;
   Promise(this.expr, this.env);
 
   /// Evaluates the promise, or returns the result if already evaluated.
-  Expression force() {
+  Value force() {
     if (!_evaluated) {
       expr = schemeEval(expr, env);
       env.interpreter.language.validateCdr(expr,

lib/src/extra/extra_library.g.dart

@@ -61,10 +61,9 @@ abstract class _$ExtraLibraryMixin {
     addBuiltin(__env, const SchemeSymbol("bindings"), (__exprs, __env) {
       return (this.bindings(__env)).list;
     }, 0,
-        docs: Docs(
-            "bindings",
-            "Returns a list of all bindings in the current environment.\n",
-            []));
+        docs: Docs("bindings",
+            "Returns a list of all bindings in the current environment.\n", [],
+            returnType: "list"));
     addVariableBuiltin(__env, const SchemeSymbol('trigger-event'),
         (__exprs, __env) {
       this.triggerEvent(__exprs, __env);

lib/src/extra/visualization.dart

@@ -11,12 +11,6 @@ class Button extends Widget {
   void Function() click;
   Widget inside;
   Button(this.inside, this.click);
-  Button.forEvent(
-      this.inside, SchemeSymbol id, List<Expression> data, Frame env) {
-    click = () {
-      env.interpreter.triggerEvent(id, data, env);
-    };
-  }
 }
 
 class Visualization extends Widget {
@@ -29,6 +23,8 @@ class Visualization extends Widget {
   List<Widget> buttonRow;
   Value result;
 
+  Function(int index, [bool keepAnimating]) goto;
+
   Visualization(this.code, this.env) {
     Interpreter inter = env.interpreter;
 
@@ -61,7 +57,7 @@ class Visualization extends Widget {
 
   _init() {
     bool animating = false;
-    goto(int index, [bool keepAnimating = false]) {
+    goto = (index, [keepAnimating = false]) {
       if (!keepAnimating) animating = false;
       if (index < 0) index = diagrams.length - 1;
       if (index >= diagrams.length - 1) {
@@ -71,7 +67,7 @@ class Visualization extends Widget {
       current = index;
       buttonRow[2] = TextWidget("${current + 1}/${diagrams.length}");
       update();
-    }
+    };
 
     Button first = Button(TextWidget("<<"), () => goto(0));
     Button prev = Button(TextWidget("<"), () => goto(current - 1));
@@ -83,6 +79,7 @@ class Visualization extends Widget {
         animating = false;
         return;
       }
+      if (current == diagrams.length - 1) goto(0);
       animating = true;
       await Future.delayed(Duration(seconds: 1));
       while (animating && current < diagrams.length - 1) {
@@ -93,7 +90,7 @@ class Visualization extends Widget {
     buttonRow = [first, prev, status, next, last, animate];
   }
 
-  void _addFrames(Frame myEnv, [Expression returnValue]) {
+  void _addFrames(Frame myEnv, [Value returnValue]) {
     if (myEnv.tag == '#imported') return;
     if (frameReturnValues.containsKey(myEnv)) {
       frameReturnValues[myEnv] = returnValue;

lib/src/web/turtle_library.dart

@@ -50,7 +50,7 @@ class TurtleLibrary extends SchemeLibrary with _$TurtleLibraryMixin {
   @turtlestart
   @MinArgs(1)
   @MaxArgs(2)
-  void circle(List<Expression> exprs) {
+  void circle(List<Value> exprs) {
     if (exprs[0] is! Number) {
       throw SchemeException('${exprs[0]} is not a number');
     }
@@ -96,7 +96,7 @@ class TurtleLibrary extends SchemeLibrary with _$TurtleLibraryMixin {
 
   /// Sets the pen color of the turtle.
   @turtlestart
-  void color(Expression color) {
+  void color(Value color) {
     turtle.penColor = Color.fromAnything(color);
   }
 
@@ -123,13 +123,13 @@ class TurtleLibrary extends SchemeLibrary with _$TurtleLibraryMixin {
 
   /// Sets the background color of the turtle canvas.
   @turtlestart
-  void bgcolor(Expression color) {
+  void bgcolor(Value color) {
     turtle.backgroundColor = Color.fromAnything(color);
   }
 
   /// Sets the [size] of the turtle's pen.
   @turtlestart
-  void pensize(num size) {
+  void pensize(int size) {
     turtle.penSize = size;
   }
 
@@ -169,7 +169,7 @@ class TurtleLibrary extends SchemeLibrary with _$TurtleLibraryMixin {
 
   /// Draws a box with [color] in the turtle's current pixel size at ([x], [y])
   @turtlestart
-  void pixel(num x, num y, Expression color) {
+  void pixel(num x, num y, Value color) {
     turtle.drawPixel(x, y, Color.fromAnything(color));
   }
 
@@ -188,7 +188,6 @@ class TurtleLibrary extends SchemeLibrary with _$TurtleLibraryMixin {
   @SchemeSymbol('screen-height')
   num screenHeight() => turtle.gridHeight / turtle.pixelSize;
 
-  /// This turtle procedure is not supported in the web interpreter.
   @SchemeSymbol('unsupported')
   @SchemeSymbol('speed')
   @SchemeSymbol('showturtle')

lib/src/web/turtle_library.g.dart

@@ -9,23 +9,23 @@ abstract class _$TurtleLibraryMixin {
   void backward(num distance);
   void left(num angle);
   void right(num angle);
-  void circle(List<Expression> exprs);
+  void circle(List<Value> exprs);
   void setPosition(num x, num y);
   void setHeading(num heading);
   void penUp();
   void penDown();
   void turtleClear();
-  void color(Expression color);
+  void color(Value color);
   void beginFill();
   void endFill();
   void exitonclick(Frame env);
   void exit();
-  void bgcolor(Expression color);
-  void pensize(num size);
+  void bgcolor(Value color);
+  void pensize(int size);
   void turtleHelp(Frame env);
   void setGridSize(int width, int height);
   void setCanvasSize(int width, int height);
-  void pixel(num x, num y, Expression color);
+  void pixel(num x, num y, Value color);
   void pixelsize(int size);
   num screenWidth();
   num screenHeight();
@@ -90,10 +90,8 @@ abstract class _$TurtleLibraryMixin {
         __env.bindings[const SchemeSymbol('right')];
     __env.hidden[const SchemeSymbol('rt')] = true;
     addVariableBuiltin(__env, const SchemeSymbol("circle"), (__exprs, __env) {
-      if (__exprs.any((x) => x is! Expression))
-        throw SchemeException('Argument of invalid type passed to circle.');
       turtle.show();
-      this.circle(__exprs.cast<Expression>());
+      this.circle(__exprs);
       return undefined;
     }, 1,
         maxArgs: 2,
@@ -153,14 +151,12 @@ abstract class _$TurtleLibraryMixin {
       return undefined;
     }, 0, docs: Docs('turtle-clear', "Clears the current turtle state.\n", []));
     addBuiltin(__env, const SchemeSymbol("color"), (__exprs, __env) {
-      if (__exprs[0] is! Expression)
-        throw SchemeException('Argument of invalid type passed to color.');
       turtle.show();
       this.color(__exprs[0]);
       return undefined;
     }, 1,
         docs: Docs("color", "Sets the pen color of the turtle.\n",
-            [Param("expression", "color")]));
+            [Param("value", "color")]));
     addBuiltin(__env, const SchemeSymbol('begin_fill'), (__exprs, __env) {
       turtle.show();
       this.beginFill();
@@ -194,25 +190,23 @@ abstract class _$TurtleLibraryMixin {
         docs: Docs('turtle-exit',
             "Closes the turtle canvas, reseting its state.\n", []));
     addBuiltin(__env, const SchemeSymbol("bgcolor"), (__exprs, __env) {
-      if (__exprs[0] is! Expression)
-        throw SchemeException('Argument of invalid type passed to bgcolor.');
       turtle.show();
       this.bgcolor(__exprs[0]);
       return undefined;
     }, 1,
         docs: Docs(
             "bgcolor",
             "Sets the background color of the turtle canvas.\n",
-            [Param("expression", "color")]));
+            [Param("value", "color")]));
     addBuiltin(__env, const SchemeSymbol("pensize"), (__exprs, __env) {
-      if (__exprs[0] is! Number)
+      if (__exprs[0] is! Integer)
         throw SchemeException('Argument of invalid type passed to pensize.');
       turtle.show();
-      this.pensize(__exprs[0].toJS());
+      this.pensize(__exprs[0].toJS().toInt());
       return undefined;
     }, 1,
         docs: Docs("pensize", "Sets the [size] of the turtle's pen.\n",
-            [Param("num", "size")]));
+            [Param("int", "size")]));
     addBuiltin(__env, const SchemeSymbol('turtle-help'), (__exprs, __env) {
       this.turtleHelp(__env);
       return undefined;
@@ -244,9 +238,7 @@ abstract class _$TurtleLibraryMixin {
             "Sets the exterior dimensions of the turtle's canvas.\n\nThis does not effect the current state of the turtle.\n",
             [Param("int", "width"), Param("int", "height")]));
     addBuiltin(__env, const SchemeSymbol("pixel"), (__exprs, __env) {
-      if (__exprs[0] is! Number ||
-          __exprs[1] is! Number ||
-          __exprs[2] is! Expression)
+      if (__exprs[0] is! Number || __exprs[1] is! Number)
         throw SchemeException('Argument of invalid type passed to pixel.');
       turtle.show();
       this.pixel(__exprs[0].toJS(), __exprs[1].toJS(), __exprs[2]);
@@ -255,11 +247,7 @@ abstract class _$TurtleLibraryMixin {
         docs: Docs(
             "pixel",
             "Draws a box with [color] in the turtle's current pixel size at ([x], [y])\n",
-            [
-              Param("num", "x"),
-              Param("num", "y"),
-              Param("expression", "color")
-            ]));
+            [Param("num", "x"), Param("num", "y"), Param("value", "color")]));
     addBuiltin(__env, const SchemeSymbol("pixelsize"), (__exprs, __env) {
       if (__exprs[0] is! Integer)
         throw SchemeException('Argument of invalid type passed to pixelsize.');
@@ -297,10 +285,7 @@ abstract class _$TurtleLibraryMixin {
             'Argument of invalid type passed to unsupported.');
       this.unsupported(__exprs.cast<Expression>(), __env);
       return undefined;
-    }, 0,
-        maxArgs: -1,
-        docs: Docs.variable('unsupported',
-            "This turtle procedure is not supported in the web interpreter.\n"));
+    }, 0, maxArgs: -1);
     __env.bindings[const SchemeSymbol('speed')] =
         __env.bindings[const SchemeSymbol('unsupported')];
     __env.hidden[const SchemeSymbol('speed')] = true;