[vala/staging: 1/3] Simplify determining the type of conditional expressions

[Jürg Billeter <juergbi src gnome org>]

commit 4a1aa7fdf6cc1b178fc35528636a70e5b51a1e57
Author: Luca Bruno <lucabru src gnome org>
Date:   Fri May 27 15:10:54 2011 +0200

    Simplify determining the type of conditional expressions
    
    https://bugzilla.gnome.org/show_bug.cgi?id=639990

 vala/valaconditionalexpression.vala |   62 +++++++++++++++-------------------
 1 files changed, 27 insertions(+), 35 deletions(-)
---
diff --git a/vala/valaconditionalexpression.vala b/vala/valaconditionalexpression.vala
index 3ae003c..a0151db 100644
--- a/vala/valaconditionalexpression.vala
+++ b/vala/valaconditionalexpression.vala
@@ -100,6 +100,16 @@ public class Vala.ConditionalExpression : Expression {
                return condition.is_pure () && true_expression.is_pure () && false_expression.is_pure ();
        }
 
+       public override void replace_expression (Expression old_node, Expression new_node) {
+               if (condition == old_node) {
+                       condition = new_node;
+               } else if (true_expression == old_node) {
+                       true_expression = new_node;
+               } else if (false_expression == old_node) {
+                       false_expression = new_node;
+               }
+       }
+
        public override bool check (CodeContext context) {
                if (checked) {
                        return !error;
@@ -118,38 +128,11 @@ public class Vala.ConditionalExpression : Expression {
 
                string temp_name = get_temp_name ();
 
-               true_expression.target_type = target_type;
-               false_expression.target_type = target_type;
-
-               var local = new LocalVariable (null, temp_name, null, source_reference);
-               var decl = new DeclarationStatement (local, source_reference);
-
-               var true_local = new LocalVariable (null, temp_name, true_expression, 
true_expression.source_reference);
-               var true_block = new Block (true_expression.source_reference);
-               var true_decl = new DeclarationStatement (true_local, true_expression.source_reference);
-               true_block.add_statement (true_decl);
-
-               var false_local = new LocalVariable (null, temp_name, false_expression, 
false_expression.source_reference);
-               var false_block = new Block (false_expression.source_reference);
-               var false_decl = new DeclarationStatement (false_local, false_expression.source_reference);
-               false_block.add_statement (false_decl);
-
-               var if_stmt = new IfStatement (condition, true_block, false_block, source_reference);
-
-               insert_statement (context.analyzer.insert_block, decl);
-               insert_statement (context.analyzer.insert_block, if_stmt);
-
-               if (!if_stmt.check (context) || true_expression.error || false_expression.error) {
+               if (!true_expression.check (context) || !false_expression.check (context)) {
                        error = true;
                        return false;
                }
 
-               true_expression = true_local.initializer;
-               false_expression = false_local.initializer;
-
-               true_block.remove_local_variable (true_local);
-               false_block.remove_local_variable (false_local);
-
                if (false_expression.value_type.compatible (true_expression.value_type)) {
                        value_type = true_expression.value_type.copy ();
                } else if (true_expression.value_type.compatible (false_expression.value_type)) {
@@ -162,20 +145,29 @@ public class Vala.ConditionalExpression : Expression {
 
                value_type.value_owned = (true_expression.value_type.value_owned || 
false_expression.value_type.value_owned);
 
-               local.variable_type = value_type;
-               decl.check (context);
-
                true_expression.target_type = value_type;
                false_expression.target_type = value_type;
 
+               var local = new LocalVariable (value_type, temp_name, null, source_reference);
+               var decl = new DeclarationStatement (local, source_reference);
+
+               var true_block = new Block (true_expression.source_reference);
                var true_stmt = new ExpressionStatement (new Assignment (new MemberAccess.simple (local.name, 
true_expression.source_reference), true_expression, AssignmentOperator.SIMPLE, 
true_expression.source_reference), true_expression.source_reference);
-               true_stmt.check (context);
+               true_block.add_statement (true_stmt);
 
+               var false_block = new Block (false_expression.source_reference);
                var false_stmt = new ExpressionStatement (new Assignment (new MemberAccess.simple 
(local.name, false_expression.source_reference), false_expression, AssignmentOperator.SIMPLE, 
false_expression.source_reference), false_expression.source_reference);
-               false_stmt.check (context);
+               false_block.add_statement (false_stmt);
 
-               true_block.replace_statement (true_decl, true_stmt);
-               false_block.replace_statement (false_decl, false_stmt);
+               var if_stmt = new IfStatement (condition, true_block, false_block, source_reference);
+
+               insert_statement (context.analyzer.insert_block, decl);
+               insert_statement (context.analyzer.insert_block, if_stmt);
+
+               if (!decl.check (context) || !if_stmt.check (context)) {
+                       error = true;
+                       return false;
+               }
 
                var ma = new MemberAccess.simple (local.name, source_reference);
                ma.formal_target_type = formal_target_type;