vala/valastringliteral.vala

   1 /* valastringliteral.vala
   2  *
   3  * Copyright (C) 2006-2011  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
  25 /**
  26  * Represents a string literal in the source code.
  27  */
  28 public class Vala.StringLiteral : Literal {
  29         /**
  30          * The literal value.
  31          */
  32         public string value { get; set; }
  33
  34         public bool translate { get; set; }
  35
  36         /**
  37          * Creates a new string literal.
  38          *
  39          * @param value             the literal value
  40          * @param source_reference  reference to source code
  41          * @return                  newly created string literal
  42          */
  43         public StringLiteral (string value, SourceReference? source_reference = null) {
  44                 this.value = value;
  45                 this.source_reference = source_reference;
  46         }
  47
  48         /**
  49          * Evaluates the literal string value.
  50          *
  51          * @return the unescaped string
  52          */
  53         public string? eval () {
  54                 if (value == null) {
  55                         return null;
  56                 }
  57
  58                 /* remove quotes */
  59                 var noquotes = value.substring (1, (uint) (value.length - 2));
  60                 /* unescape string */
  61                 return noquotes.compress ();
  62         }
  63
  64         public override void accept (CodeVisitor visitor) {
  65                 visitor.visit_string_literal (this);
  66
  67                 visitor.visit_expression (this);
  68         }
  69
  70         public override bool is_pure () {
  71                 return true;
  72         }
  73
  74         public override bool is_non_null () {
  75                 return true;
  76         }
  77
  78         public override string to_string () {
  79                 return value;
  80         }
  81
  82         public override bool check (CodeContext context) {
  83                 if (checked) {
  84                         return !error;
  85                 }
  86
  87                 checked = true;
  88
  89                 value_type = context.analyzer.string_type.copy ();
  90
  91                 return !error;
  92         }
  93
  94         public override void emit (CodeGenerator codegen) {
  95                 codegen.visit_string_literal (this);
  96
  97                 codegen.visit_expression (this);
  98         }
  99
 100         public static StringLiteral? get_format_literal (Expression expr) {
 101                 var format_literal = expr as StringLiteral;
 102                 if (format_literal != null) {
 103                         return format_literal;
 104                 }
 105
 106                 var call = expr as MethodCall;
 107                 if (call != null) {
 108                         return call.get_format_literal ();
 109                 }
 110
 111                 return null;
 112         }
 113 }