vala/valacharacterliteral.vala

   1 /* valacharacterliteral.vala
   2  *
   3  * Copyright (C) 2006-2010  Jürg Billeter
   4  * Copyright (C) 2006-2009  Raffaele Sandrini
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
  19  *
  20  * Author:
  21  *      Jürg Billeter <j@bitron.ch>
  22  *      Raffaele Sandrini <raffaele@sandrini.ch>
  23  */
  24
  25 using GLib;
  26
  27 /**
  28  * Represents a single literal character.
  29  */
  30 public class Vala.CharacterLiteral : Literal {
  31         /**
  32          * The literal value.
  33          */
  34         public string value {
  35                 get {
  36                         return _value;
  37                 }
  38                 set {
  39                         _value = value;
  40
  41                         if (!value.validate ()) {
  42                                 error = true;
  43                         }
  44                 }
  45         }
  46
  47         private string _value;
  48
  49         /**
  50          * Creates a new character literal.
  51          *
  52          * @param c      character
  53          * @param source reference to source code
  54          * @return       newly created character literal
  55          */
  56         public CharacterLiteral (string c, SourceReference? source = null) {
  57                 value = c;
  58                 source_reference = source;
  59
  60         }
  61
  62         public override void accept (CodeVisitor visitor) {
  63                 visitor.visit_character_literal (this);
  64
  65                 visitor.visit_expression (this);
  66         }
  67
  68         /**
  69          * Returns the unicode character value this character literal
  70          * represents.
  71          *
  72          * @return unicode character value
  73          */
  74         public unichar get_char () {
  75                 return value.next_char ().get_char ();
  76         }
  77
  78         public override bool is_pure () {
  79                 return true;
  80         }
  81
  82         public override string to_string () {
  83                 return value;
  84         }
  85
  86         public override bool check (CodeContext context) {
  87                 if (checked) {
  88                         return !error;
  89                 }
  90
  91                 checked = true;
  92
  93                 if (get_char () < 128) {
  94                         value_type = new IntegerType ((Struct) context.root.scope.lookup ("char"));
  95                 } else {
  96                         value_type = new IntegerType ((Struct) context.root.scope.lookup ("unichar"));
  97                 }
  98
  99                 return !error;
 100         }
 101
 102         public override void emit (CodeGenerator codegen) {
 103                 codegen.visit_character_literal (this);
 104
 105                 codegen.visit_expression (this);
 106         }
 107 }