Add support for implicitly concatenating adjacent string literals.

frog/minfrog

 #!/usr/bin/env node
 //  ********** Library dart:core **************
 //  ********** Natives dart:core **************
 function $defProp(obj, prop, value) {
   Object.defineProperty(obj, prop,
       {value: value, enumerable: false, writable: true, configurable: true});
 }
 Function.prototype.bind = Function.prototype.bind ||
   function(thisObj) {
     var func = this;
@@ skipping 2633 matching lines @@
 }
 MethodAnalyzer.prototype.visitThisExpression = function(node) {
   return this._frame.makeThisValue(node);
 }
 MethodAnalyzer.prototype.visitSuperExpression = function(node) {
   return this._frame.makeSuperValue(node);
 }
 MethodAnalyzer.prototype.visitLiteralExpression = function(node) {
   return new PureStaticValue(node.value.get$type(), node.span, true, false);
 }
+MethodAnalyzer.prototype.visitStringConcatExpression = function(node) {
+  node.strings.forEach(this.get$visitValue());
+  return this._frame._makeValue($globals.world.stringType, node);
+}
 MethodAnalyzer.prototype.visitStringInterpExpression = function(node) {
   node.pieces.forEach(this.get$visitValue());
   return this._frame._makeValue($globals.world.stringType, node);
 }
 MethodAnalyzer.prototype._pushBlock$1 = MethodAnalyzer.prototype._pushBlock;
 MethodAnalyzer.prototype.analyze$1 = MethodAnalyzer.prototype.analyze;
 MethodAnalyzer.prototype.visitBinaryExpression$1 = function($0) {
   return this.visitBinaryExpression($0, false);
 };
 MethodAnalyzer.prototype.visitCallExpression$1 = function($0) {
@@ skipping 2465 matching lines @@
 }
 MethodGenerator.prototype._isUnaryIncrement = function(item) {
   if ((item instanceof UnaryExpression)) {
     var u = item;
     return u.op.kind == (16) || u.op.kind == (17);
   }
   else {
     return false;
   }
 }
+MethodGenerator.prototype.visitStringConcatExpression = function(node) {
+  var items = [];
+  var $$list = node.strings;
+  for (var $$i = $$list.iterator(); $$i.hasNext(); ) {
+    var item = $$i.next();
+    var val = this.visitValue(item);
+    items.add(val.get$code());
+  }
+  return new Value($globals.world.stringType, ("(" + Strings.join(items, " + ") + ")"), node.span);
+}
 MethodGenerator.prototype.visitStringInterpExpression = function(node) {
   var items = [];
   var $$list = node.pieces;
   for (var $$i = $$list.iterator(); $$i.hasNext(); ) {
     var item = $$i.next();
     var val = this.visitValue(item);
     val.invoke(this, "toString", item, Arguments.get$EMPTY());
     var code = val.get$code();
     if (this._expressionNeedsParens(item)) {
       code = ("(" + code + ")");
@@ skipping 5016 matching lines @@
 
       var t = this._lang_next();
       return this._makeLiteral(Value.fromInt(Math.parseInt(t.get$text()), t.get$span()));
 
     case (62):
 
       var t = this._lang_next();
       return this._makeLiteral(Value.fromDouble(Math.parseDouble(t.get$text()), t.get$span()));
 
     case (58):
-
-      var t = this._lang_next();
-      return this._makeLiteral(Value.fromString(t.get$value(), t.get$span()));
-
     case (59):
 
-      return this.stringInterpolation();
+      return this.adjacentStrings();
 
     case (52):
 
       return this.finishTypedLiteral(start, false);
 
     case (115):
     case (114):
     case (99):
 
       return this.declaredIdentifier(false);
 
     default:
 
       if (!this._peekIdentifier()) {
         this._errorExpected("expression");
       }
       return new VarExpression(this.identifier(), this._makeSpan(start));
 
   }
 }
+Parser.prototype.adjacentStrings = function() {
+  var start = this._peekToken.start;
+  var strings = [];
+  while (this._peek() == (58) || this._peek() == (59)) {
+    var part = null;
+    if (this._peek() == (58)) {
+      var t = this._lang_next();
+      part = this._makeLiteral(Value.fromString(t.get$value(), t.get$span()));
+    }
+    else {
+      part = this.stringInterpolation();
+    }
+    strings.add(part);
+  }
+  if (strings.get$length() == (1)) {
+    return strings.$index((0));
+  }
+  else {
+    return new StringConcatExpression(strings, this._makeSpan(start));
+  }
+}
 Parser.prototype.stringInterpolation = function() {
   var start = this._peekToken.start;
   var pieces = new Array();
   var startQuote = null, endQuote = null;
   while (this._peekKind((59))) {
     var token = this._lang_next();
     pieces.add(this._makeLiteral(Value.fromString(token.get$value(), token.get$span())));
     if (this._maybeEat((6))) {
       pieces.add(this.expression());
       this._eat((7));
@@ skipping 1026 matching lines @@
 $inherits(LiteralExpression, Expression);
 function LiteralExpression(value, span) {
   this.value = value;
   Expression.call(this, span);
 }
 LiteralExpression.prototype.get$value = function() { return this.value; };
 LiteralExpression.prototype.set$value = function(value) { return this.value = value; };
 LiteralExpression.prototype.visit = function(visitor) {
   return visitor.visitLiteralExpression(this);
 }
+// ********** Code for StringConcatExpression **************
+$inherits(StringConcatExpression, Expression);
+function StringConcatExpression(strings, span) {
+  this.strings = strings;
+  Expression.call(this, span);
+}
+StringConcatExpression.prototype.visit = function(visitor) {
+  return visitor.visitStringConcatExpression(this);
+}
 // ********** Code for StringInterpExpression **************
 $inherits(StringInterpExpression, Expression);
 function StringInterpExpression(pieces, span) {
   this.pieces = pieces;
   Expression.call(this, span);
 }
 StringInterpExpression.prototype.visit = function(visitor) {
   return visitor.visitStringInterpExpression(this);
 }
 // ********** Code for SimpleTypeReference **************
@@ skipping 3647 matching lines @@
 var const$0002 = Object.create(EmptyQueueException.prototype, {});
 var const$0006 = Object.create(IllegalAccessException.prototype, {});
 var const$0007 = ImmutableList.ImmutableList$from$factory([]);
 var const$0009 = new JSSyntaxRegExp("^[a-zA-Z]:/");
 var const$0010 = ImmutableList.ImmutableList$from$factory(["__PROTO__", "prototype", "constructor"]);
 var const$0011 = ImmutableList.ImmutableList$from$factory(["NaN", "Infinity", "undefined", "eval", "parseInt", "parseFloat", "isNan", "isFinite", "decodeURI", "decodeURIComponent", "encodeURI", "encodeURIComponent", "Object", "Function", "Array", "String", "Boolean", "Number", "Date", "RegExp", "Error", "EvalError", "RangeError", "ReferenceError", "SyntaxError", "TypeError", "URIError", "Math", "arguments", "escape", "unescape", "applicationCache", "closed", "Components", "content", "controllers", "crypto", "defaultStatus", "dialogArguments", "directories", "document", "frameElement", "frames", "fullScreen", "globalStorage", "history", "innerHeight", "innerWidth", "length", "location", "locationbar", "localStorage", "menubar", "mozInnerScreenX", "mozInnerScreenY", "mozScreenPixelsPerCssPixel", "name", "navigator", "opener", "outerHeight", "outerWidth", "pageXOffset", "pageYOffset", "parent", "personalbar", "pkcs11", "returnValue", "screen", "scrollbars", "scrollMaxX", "scrollMaxY", "self", "sessionStorage", "sidebar", "status", "statusbar", "toolbar", "top", "window", "alert", "addEventListener", "atob", "back", "blur", "btoa", "captureEvents", "clearInterval", "clearTimeout", "close", "confirm", "disableExternalCapture", "dispatchEvent", "dump", "enableExternalCapture", "escape", "find", "focus", "forward", "GeckoActiveXObject", "getAttention", "getAttentionWithCycleCount", "getComputedStyle", "getSelection", "home", "maximize", "minimize", "moveBy", "moveTo", "open", "openDialog", "postMessage", "print", "prompt", "QueryInterface", "releaseEvents", "removeEventListener", "resizeBy", "resizeTo", "restore", "routeEvent", "scroll", "scrollBy", "scrollByLines", "scrollByPages", "scrollTo", "setInterval", "setResizeable", "setTimeout", "showModalDialog", "sizeToContent", "stop", "uuescape", "updateCommands", "XPCNativeWrapper", "XPCSafeJSOjbectWrapper", "onabort", "onbeforeunload", "onchange", "onclick", "onclose", "oncontextmenu", "ondragdrop", "onerror", "onfocus", "onhashchange", "onkeydown", "onkeypress", "onkeyup", "onload", "onmousedown", "onmousemove", "onmouseout", "onmouseover", "onmouseup", "onmozorientation", "onpaint", "onreset", "onresize", "onscroll", "onselect", "onsubmit", "onunload", "ontouchcancel", "ontouchend", "ontouchmove", "ontouchstart", "ongesturestart", "ongesturechange", "ongestureend", "uneval", "getPrototypeOf", "let", "yield", "abstract", "int", "short", "boolean", "interface", "static", "byte", "long", "char", "final", "native", "synchronized", "float", "package", "throws", "goto", "private", "transient", "implements", "protected", "volatile", "double", "public", "attachEvent", "clientInformation", "clipboardData", "createPopup", "dialogHeight", "dialogLeft", "dialogTop", "dialogWidth", "onafterprint", "onbeforedeactivate", "onbeforeprint", "oncontrolselect", "ondeactivate", "onhelp", "onresizeend", "event", "external", "Debug", "Enumerator", "Global", "Image", "ActiveXObject", "VBArray", "Components", "toString", "getClass", "constructor", "prototype", "valueOf", "Anchor", "Applet", "Attr", "Canvas", "CanvasGradient", "CanvasPattern", "CanvasRenderingContext2D", "CDATASection", "CharacterData", "Comment", "CSS2Properties", "CSSRule", "CSSStyleSheet", "Document", "DocumentFragment", "DocumentType", "DOMException", "DOMImplementation", "DOMParser", "Element", "Event", "ExternalInterface", "FlashPlayer", "Form", "Frame", "History", "HTMLCollection", "HTMLDocument", "HTMLElement", "IFrame", "Image", "Input", "JSObject", "KeyEvent", "Link", "Location", "MimeType", "MouseEvent", "Navigator", "Node", "NodeList", "Option", "Plugin", "ProcessingInstruction", "Range", "RangeException", "Screen", "Select", "Table", "TableCell", "TableRow", "TableSelection", "Text", "TextArea", "UIEvent", "Window", "XMLHttpRequest", "XMLSerializer", "XPathException", "XPathResult", "XSLTProcessor", "java", "Packages", "netscape", "sun", "JavaObject", "JavaClass", "JavaArray", "JavaMember", "$wnd", "$doc", "$entry", "$moduleName", "$moduleBase", "$gwt_version", "$sessionId", "$stack", "$stackDepth", "$location", "call"]);
 var const$0012 = ImmutableList.ImmutableList$from$factory(["break", "delete", "function", "return", "typeof", "case", "do", "if", "switch", "var", "catch", "else", "in", "this", "void", "continue", "false", "instanceof", "throw", "while", "debugger", "finally", "new", "true", "with", "default", "for", "null", "try", "abstract", "double", "goto", "native", "static", "boolean", "enum", "implements", "package", "super", "byte", "export", "import", "private", "synchronized", "char", "extends", "int", "protected", "throws", "class", "final", "interface", "public", "transient", "const", "float", "long", "short", "volatile"]);
 var $globals = {};
 $static_init();
 main();