Convert raw strings in compiler

lib/compiler/implementation/js_backend/constant_emitter.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class ConstantEmitter implements ConstantVisitor {
   final Compiler compiler;
   final Namer namer;
 
   CodeBuffer buffer;
   bool shouldEmitCanonicalVersion;
@@ skipping 76 matching lines @@
    * a form that is valid as JavaScript string literal content.
    * The string is assumed quoted by single quote characters.
    */
   void writeEscapedString(DartString string,
                           CodeBuffer buffer,
                           Node diagnosticNode) {
     Iterator<int> iterator = string.iterator();
     while (iterator.hasNext()) {
       int code = iterator.next();
       if (code === $SQ) {
-        buffer.add(@"\'");
+        buffer.add(r"\'");
       } else if (code === $LF) {
-        buffer.add(@'\n');
+        buffer.add(r'\n');
       } else if (code === $CR) {
-        buffer.add(@'\r');
+        buffer.add(r'\r');
       } else if (code === $LS) {
         // This Unicode line terminator and $PS are invalid in JS string
         // literals.
-        buffer.add(@'\u2028');
+        buffer.add(r'\u2028');
       } else if (code === $PS) {
-        buffer.add(@'\u2029');
+        buffer.add(r'\u2029');
       } else if (code === $BACKSLASH) {
-        buffer.add(@'\\');
+        buffer.add(r'\\');
       } else {
         if (code > 0xffff) {
           compiler.reportError(
               diagnosticNode,
               'Unhandled non-BMP character: U+${code.toRadixString(16)}');
         }
         // TODO(lrn): Consider whether all codes above 0x7f really need to
         // be escaped. We build a Dart string here, so it should be a literal
         // stage that converts it to, e.g., UTF-8 for a JS interpreter.
         if (code < 0x20) {
-          buffer.add(@'\x');
+          buffer.add(r'\x');
           if (code < 0x10) buffer.add('0');
           buffer.add(code.toRadixString(16));
         } else if (code >= 0x80) {
           if (code < 0x100) {
-            buffer.add(@'\x');
+            buffer.add(r'\x');
           } else {
-            buffer.add(@'\u');
+            buffer.add(r'\u');
             if (code < 0x1000) {
               buffer.add('0');
             }
           }
           buffer.add(code.toRadixString(16));
         } else {
           buffer.addCharCode(code);
         }
       }
     }
@@ skipping 105 matching lines @@
       buffer.add(getJsConstructor(constant.type.element));
       buffer.add("(");
       for (int i = 0; i < constant.fields.length; i++) {
         if (i != 0) buffer.add(", ");
         _visit(constant.fields[i]);
       }
       buffer.add(")");
     }
   }
 }