Lazy implementation of final variables.

lib/compiler/implementation/compiler.dart

Index: lib/compiler/implementation/compiler.dart
diff --git a/lib/compiler/implementation/compiler.dart b/lib/compiler/implementation/compiler.dart
index 2725e1ee675e5d6e25329c38a68942a594538b74..c5998d9a6fd165d8e9d7cf6e00cd4dc064a67122 100644
--- a/lib/compiler/implementation/compiler.dart
+++ b/lib/compiler/implementation/compiler.dart
@@ -765,10 +765,13 @@ class Compiler implements DiagnosticListener {
       progress.reset();
     }
     if (work.element.kind.category == ElementCategory.VARIABLE) {
-      constantHandler.compileWorkItem(work);
-    } else {
-      backend.codegen(work);
+      Constant initialValue = constantHandler.compileWorkItem(work);
+      if (initialValue != null) return;

[kasperl, 2012/08/17 09:30:04]

!==

[floitsch, 2012/09/04 17:32:21]

Done.

+      // If the constant-handler was not able to produce a result we have to
+      // go through the builder (below) to generate the lazy initializer for
+      // the static variable.
     }
+    backend.codegen(work);
   }
 
   void registerInstantiatedClass(ClassElement cls) {
@@ -802,6 +805,18 @@ class Compiler implements DiagnosticListener {
         () => resolver.computeFunctionType(element, signature));
   }
 
+  bool isLazilyInitialized(VariableElement element) {
+    Constant initialValue = compileVariable(element);
+    return initialValue === null;
+  }
+
+  /** Compiles compile-time constants. Must not return `null`. */
+  Constant compileConstant(VariableElement element) {
+    return withCurrentElement(element, () {
+      return constantHandler.compileConstant(element);
+    });
+  }
+
   Constant compileVariable(VariableElement element) {
     return withCurrentElement(element, () {
       return constantHandler.compileVariable(element);