vala/valablock.vala

   1 /* valablock.vala
   2  *
   3  * Copyright (C) 2006-2008  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 using GLib;
  24 using Gee;
  25
  26 /**
  27  * Represents a source code block.
  28  */
  29 public class Vala.Block : Symbol, Statement {
  30         /**
  31          * Specifies whether this block contains a jump statement. This
  32          * information can be used to remove unreachable block cleanup code.
  33          */
  34         public bool contains_jump_statement { get; set; }
  35
  36         private Gee.List<Statement> statement_list = new ArrayList<Statement> ();
  37         private Gee.List<LocalVariable> local_variables = new ArrayList<LocalVariable> ();
  38
  39         /**
  40          * Creates a new block.
  41          *
  42          * @param source reference to source code
  43          */
  44         public Block (SourceReference source_reference) {
  45                 base (null, source_reference);
  46         }
  47
  48         /**
  49          * Append a statement to this block.
  50          *
  51          * @param stmt a statement
  52          */
  53         public void add_statement (Statement stmt) {
  54                 statement_list.add (stmt);
  55         }
  56
  57         /**
  58          * Returns a copy of the list of statements.
  59          *
  60          * @return statement list
  61          */
  62         public Gee.List<Statement> get_statements () {
  63                 return new ReadOnlyList<Statement> (statement_list);
  64         }
  65
  66         /**
  67          * Add a local variable to this block.
  68          *
  69          * @param decl a variable declarator
  70          */
  71         public void add_local_variable (LocalVariable local) {
  72                 local_variables.add (local);
  73         }
  74
  75         /**
  76          * Returns a copy of the list of local variables.
  77          *
  78          * @return variable declarator list
  79          */
  80         public Gee.List<LocalVariable> get_local_variables () {
  81                 return new ReadOnlyList<LocalVariable> (local_variables);
  82         }
  83
  84         public override void accept (CodeVisitor visitor) {
  85                 visitor.visit_block (this);
  86         }
  87
  88         public override void accept_children (CodeVisitor visitor) {
  89                 foreach (Statement stmt in statement_list) {
  90                         stmt.accept (visitor);
  91                 }
  92         }
  93
  94         public override bool check (SemanticAnalyzer analyzer) {
  95                 if (checked) {
  96                         return !error;
  97                 }
  98
  99                 checked = true;
 100
 101                 owner = analyzer.current_symbol.scope;
 102                 analyzer.current_symbol = this;
 103
 104                 foreach (Statement stmt in statement_list) {
 105                         stmt.check (analyzer);
 106                 }
 107
 108                 foreach (LocalVariable local in get_local_variables ()) {
 109                         local.active = false;
 110                 }
 111
 112                 foreach (Statement stmt in get_statements ()) {
 113                         add_error_types (stmt.get_error_types ());
 114                 }
 115
 116                 analyzer.current_symbol = analyzer.current_symbol.parent_symbol;
 117
 118                 return !error;
 119         }
 120 }