/****************************************************************************
**
** Explanation of tqmoc and the meta object system
**
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/*!
\page metaobjects.html

\title Meta Object System

\keyword meta object
\keyword TQ_OBJECT

Qt's Meta Object System provides the signals and slots mechanism for
inter-object communication, runtime type information, and the dynamic
property system.

The Meta Object System is based on three things:
\list 1
\i the \l TQObject class;
\i the TQ_OBJECT macro inside the private section of the class
declaration;
\i the \link tqmoc.html Meta Object Compiler (tqmoc)\endlink. 
\endlist

\e TQMoc reads a C++ source file. If it finds one or more class
declarations that contain the TQ_OBJECT macro, it produces another C++
source file which contains the meta object code for the classes that
contain the TQ_OBJECT macro. This generated source file is either
#included into the class's source file or compiled and linked with the
class's implementation.

In addition to providing the \link signalsandslots.html signals and
slots \endlink mechanism for communication between objects (the main
reason for introducing the system), the meta object code provides
additional features in TQObject:

\list

\i the \link TQObject::className() className() \endlink function that
returns the class name as a string at runtime, without requiring
native runtime type information (RTTI) support through the C++
compiler.

\i the \link TQObject::inherits() inherits() \endlink function that
returns whether an object is an instance of a class that inherits a
specified class within the TQObject inheritance tree.

\i the \link TQObject::tr() tr() \endlink and
\link TQObject::trUtf8() trUtf8() \endlink functions for string
translation as used for internationalization.

\i the \link TQObject::setProperty() setProperty() \endlink and \link
TQObject::property() property() \endlink functions for dynamically
setting and getting \link properties.html object properties\endlink by
name.

\i the \link TQObject::metaObject() metaObject() \endlink function that
returns the associated \link TQMetaObject meta object \endlink for the
class.

\endlist

While it is possible to use TQObject as a base class without the
TQ_OBJECT macro and without meta object code, neither signals and slots
nor the other features described here will be available if the
TQ_OBJECT macro is not used. From the meta object system's point of
view, a TQObject subclass without meta code is equivalent to its
closest ancestor with meta object code. This means for example, that
className() will not return the actual name of your class, but the
class name of this ancestor. We \e strongly recommend that all
subclasses of TQObject use the TQ_OBJECT macro regardless of whether
they actually use signals, slots and properties or not.

*/