mcs/class/System.ServiceModel/Mono.CodeGeneration/CodeForeach.cs

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   4 // "Software"), to deal in the Software without restriction, including
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   7 // permit persons to whom the Software is furnished to do so, subject to
   8 // the following conditions:
   9 //
  10 // The above copyright notice and this permission notice shall be
  11 // included in all copies or substantial portions of the Software.
  12 //
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  14 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  15 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  16 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  17 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  18 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  19 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  20 //
  21 // Copyright (C) Lluis Sanchez Gual, 2004
  22 //
  23
  24 #if !FULL_AOT_RUNTIME
  25 using System;
  26 using System.Collections;
  27 using System.Reflection;
  28 using System.Reflection.Emit;
  29
  30 namespace Mono.CodeGeneration
  31 {
  32         public class CodeForeach: CodeStatement
  33         {
  34                 Type itemType;
  35                 CodeExpression array;
  36                 CodeBlock forBlock;
  37
  38                 CodeVariableDeclaration itemDec;
  39
  40                 public CodeForeach (CodeExpression array, Type itemType)
  41                 {
  42                         this.array = array;
  43                         this.itemType = itemType;
  44
  45                         Type t = array.GetResultType ();
  46                         if (!t.IsArray && t.GetMethod ("GetEnumerator", Type.EmptyTypes) == null)
  47                                 throw new InvalidOperationException ("foreach statement cannot operate on variables of type `" + t + "' because that class does not provide a GetEnumerator method or it is inaccessible");
  48
  49                         itemDec = new CodeVariableDeclaration (itemType, "item");
  50                 }
  51
  52                 public CodeValueReference ItemExpression
  53                 {
  54                         get { return itemDec.Variable; }
  55                 }
  56
  57                 public CodeBlock ForBlock
  58                 {
  59                         get { return forBlock; }
  60                         set { forBlock = value; }
  61                 }
  62
  63                 public override void Generate (ILGenerator gen)
  64                 {
  65                         Type t = array.GetResultType ();
  66                         if (t.IsArray)
  67                         {
  68                                 CodeBlock block = new CodeBlock();
  69                                 CodeVariableDeclaration indexDec;
  70                                 CodeWhile cw;
  71                                 CodeValueReference index;
  72                                 CodeValueReference item;
  73
  74                                 block.Add (itemDec);
  75                                 item = itemDec.Variable;
  76                                 block.Add (indexDec = new CodeVariableDeclaration (typeof(int), "n"));
  77                                 index = indexDec.Variable;
  78                                 block.Add (new CodeAssignment (index, new CodeLiteral (0)));
  79
  80                                 block.Add (cw = new CodeWhile (CodeExpression.IsSmallerThan (index, array.ArrayLength)));
  81                                 CodeBlock loopBlock = new CodeBlock ();
  82                                 loopBlock.Add (new CodeAssignment (item, array[index]));
  83                                 loopBlock.Add (new CodeIncrement(index));
  84                                 loopBlock.Add (forBlock);
  85                                 cw.WhileBlock = loopBlock;
  86
  87                                 block.Generate (gen);
  88                         }
  89                         else
  90                         {
  91                                 CodeBlock block = new CodeBlock();
  92                                 CodeVariableDeclaration dec;
  93                                 CodeWhile cw;
  94                                 CodeValueReference enumerator;
  95                                 CodeValueReference item;
  96
  97                                 block.Add (itemDec);
  98                                 item = itemDec.Variable;
  99                                 block.Add (dec = new CodeVariableDeclaration (typeof(IEnumerator), "e"));
 100                                 enumerator = dec.Variable;
 101                                 block.Add (new CodeAssignment (enumerator, array.Call("GetEnumerator")));
 102
 103                                 block.Add (cw = new CodeWhile (enumerator.Call ("MoveNext")));
 104                                 CodeBlock loopBlock = new CodeBlock ();
 105                                 loopBlock.Add (new CodeAssignment (item, enumerator["Current"]));
 106                                 loopBlock.Add (forBlock);
 107                                 cw.WhileBlock = loopBlock;
 108
 109                                 block.Generate (gen);
 110                         }
 111                 }
 112
 113                 public override void PrintCode (CodeWriter cp)
 114                 {
 115                         cp.Write ("foreach (" + itemType + " item in ");
 116                         array.PrintCode (cp);
 117                         cp.Write (") {");
 118                         cp.EndLine ();
 119                         cp.Indent ();
 120                         forBlock.PrintCode (cp);
 121                         cp.Unindent ();
 122                         cp.BeginLine ().Write ("}");
 123                 }
 124         }
 125 }
 126 #endif