MonoRail/Castle.MonoRail.Views.Brail/ReplaceUknownWithParameters.cs

   1 // Copyright 2004-2008 Castle Project - http://www.castleproject.org/
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 namespace Castle.MonoRail.Views.Brail
  16 {
  17         using Boo.Lang.Compiler.Ast;
  18         using Boo.Lang.Compiler.Steps;
  19         using Boo.Lang.Compiler.TypeSystem;
  20
  21         ///<summary>
  22         /// Replace any uknown identifier with a call to GetParameter('unknown')
  23         /// this mean that unknonw identifier in scripts will only fail in run time if they
  24         /// were not defined by the controller.
  25         /// </summary>
  26         public class ReplaceUknownWithParameters : ProcessMethodBodiesWithDuckTyping
  27         {
  28                 private IMethod getParam;
  29                 private IMethod tryGetParam;
  30
  31                 public override void OnReferenceExpression(ReferenceExpression node)
  32                 {
  33                         IEntity entity = NameResolutionService.Resolve(node.Name);
  34                         if (entity != null)
  35                         {
  36                                 base.OnReferenceExpression(node);
  37                         }
  38                         else
  39                         {
  40                                 MethodInvocationExpression mie = CodeBuilder.CreateMethodInvocation(
  41                                         CodeBuilder.CreateSelfReference(_currentMethod.DeclaringType),
  42                                         GetMethod(node.Name));
  43                                 mie.Arguments.Add(GetNameLiteral(node.Name));
  44                                 node.ParentNode.Replace(node, mie);
  45                         }
  46                 }
  47
  48                 protected override void InitializeMemberCache()
  49                 {
  50                         base.InitializeMemberCache();
  51                         getParam = TypeSystemServices.Map(typeof(BrailBase).GetMethod("GetParameter"));
  52                         tryGetParam = TypeSystemServices.Map(typeof(BrailBase).GetMethod("TryGetParameter"));
  53                 }
  54
  55                 public IMethod GetMethod(string name)
  56                 {
  57                         if (name[0] == '?')
  58                                 return tryGetParam;
  59                         else
  60                                 return getParam;
  61                 }
  62
  63                 public StringLiteralExpression GetNameLiteral(string name)
  64                 {
  65                         if (name[0] == '?')
  66                                 return CodeBuilder.CreateStringLiteral(name.Substring(1));
  67                         else
  68                                 return CodeBuilder.CreateStringLiteral(name);
  69                 }
  70         }
  71 }