vala/valadeclarationstatement.vala

   1 /* valadeclarationstatement.vala
   2  *
   3  * Copyright (C) 2006-2010  Jürg Billeter
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  18  *
  19  * Author:
  20  *      Jürg Billeter <j@bitron.ch>
  21  */
  22
  23
  24 /**
  25  * Represents a local variable or constant declaration statement in the source code.
  26  */
  27 public class Vala.DeclarationStatement : CodeNode, Statement {
  28         /**
  29          * The local variable or constant declaration.
  30          */
  31         public Symbol declaration {
  32                 get {
  33                         return _declaration;
  34                 }
  35                 set {
  36                         _declaration = value;
  37                         if (_declaration != null) {
  38                                 _declaration.parent_node = this;
  39                         }
  40                 }
  41         }
  42
  43         Symbol _declaration;
  44
  45         /**
  46          * Creates a new declaration statement.
  47          *
  48          * @param declaration       local variable declaration
  49          * @param source_reference  reference to source code
  50          * @return                  newly created declaration statement
  51          */
  52         public DeclarationStatement (Symbol declaration, SourceReference? source_reference) {
  53                 this.declaration = declaration;
  54                 this.source_reference = source_reference;
  55         }
  56
  57         public override void accept (CodeVisitor visitor) {
  58                 visitor.visit_declaration_statement (this);
  59         }
  60
  61         public override void accept_children (CodeVisitor visitor) {
  62                 declaration.accept (visitor);
  63         }
  64
  65         public override bool check (CodeContext context) {
  66                 if (checked) {
  67                         return !error;
  68                 }
  69
  70                 checked = true;
  71
  72                 declaration.check (context);
  73
  74                 var local = declaration as LocalVariable;
  75                 if (local != null && local.initializer != null) {
  76                         foreach (DataType error_type in local.initializer.get_error_types ()) {
  77                                 // ensure we can trace back which expression may throw errors of this type
  78                                 var initializer_error_type = error_type.copy ();
  79                                 initializer_error_type.source_reference = local.initializer.source_reference;
  80
  81                                 add_error_type (initializer_error_type);
  82                         }
  83                 }
  84
  85                 return !error;
  86         }
  87
  88         public override void emit (CodeGenerator codegen) {
  89                 codegen.visit_declaration_statement (this);
  90         }
  91
  92         public override void get_defined_variables (Collection<Variable> collection) {
  93                 var local = declaration as LocalVariable;
  94                 if (local != null) {
  95                         var array_type = local.variable_type as ArrayType;
  96                         if (local.initializer != null) {
  97                                 local.initializer.get_defined_variables (collection);
  98                                 collection.add (local);
  99                         } else if (array_type != null && array_type.fixed_length) {
 100                                 collection.add (local);
 101                         }
 102                 }
 103         }
 104
 105         public override void get_used_variables (Collection<Variable> collection) {
 106                 var local = declaration as LocalVariable;
 107                 if (local != null && local.initializer != null) {
 108                         local.initializer.get_used_variables (collection);
 109                 }
 110         }
 111 }