adg/adg-util.c

   1 /* ADG - Automatic Drawing Generation
   2  * Copyright (C) 2007,2008,2009 Nicola Fontana <ntd at entidi.it>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301, USA.
  18  */
  19
  20
  21 /**
  22  * SECTION:adg-util
  23  * @title: Utilities
  24  * @short_description: Assorted macros and utilities
  25  *
  26  * A collection of macros and functions that do not fit inside any other topic.
  27  **/
  28
  29 /**
  30  * ADG_FORWARD_DECL:
  31  * @id: The name of a struct
  32  *
  33  * Forward declaration of struct @id. For example,
  34  * <code>ADG_FORWARD_DECL(test)</code> will expand to:
  35  *
  36  * <informalexample><programlisting>
  37  * typedef struct _test test
  38  * </programlisting></informalexample>
  39  *
  40  * This macro is useful to trick <command>gtk-doc</command>, as up
  41  * to now (v.1.12) it generates two conflicting links when using
  42  * forward declarations: the first in the source with the declaration
  43  * and the second where the type is defined. Using ADG_FORWARD_DECL()
  44  * instead of the usual typedef avoids the parsing of the declaration
  45  * in the first file (<command>gtk-doc</command> is not able to do C
  46  * preprocessing).
  47  *
  48  * The same principle can be applied in the definition file. Following
  49  * the previous example, you can use something like this where struct
  50  * _type is defined:
  51  *
  52  * <informalexample><programlisting>
  53  * #if 0
  54  * // This is declared in another file
  55  * typedef struct _type type;
  56  * #endif
  57  * struct _type {
  58  * ...
  59  * };
  60  * </programlisting></informalexample>
  61  **/