2 // ParameterExpression.cs
5 // Jb Evain (jbevain@novell.com)
6 // Miguel de Icaza (miguel@novell.com)
8 // (C) 2008 Novell, Inc. (http://www.novell.com)
10 // Permission is hereby granted, free of charge, to any person obtaining
11 // a copy of this software and associated documentation files (the
12 // "Software"), to deal in the Software without restriction, including
13 // without limitation the rights to use, copy, modify, merge, publish,
14 // distribute, sublicense, and/or sell copies of the Software, and to
15 // permit persons to whom the Software is furnished to do so, subject to
16 // the following conditions:
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
31 using System.Reflection.Emit;
33 namespace System.Linq.Expressions {
35 public sealed class ParameterExpression : Expression {
43 internal ParameterExpression (Type type, string name)
44 : base (ExpressionType.Parameter, type)
50 void EmitLocalParameter (EmitContext ec, int position)
52 ec.ig.Emit (OpCodes.Ldarg, position);
55 void EmitHoistedLocal (EmitContext ec, int level, int position)
59 for (int i = 0; i < level; i++)
60 ec.EmitParentScope ();
64 ec.ig.Emit (OpCodes.Ldc_I4, position);
65 ec.ig.Emit (OpCodes.Ldelem, typeof (object));
67 ec.EmitLoadStrongBoxValue (Type);
70 internal override void Emit (EmitContext ec)
73 if (ec.IsLocalParameter (this, ref position)) {
74 EmitLocalParameter (ec, position);
79 if (ec.IsHoistedLocal (this, ref level, ref position)) {
80 EmitHoistedLocal (ec, level, position);
84 throw new InvalidOperationException ("Parameter out of scope");