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/*!
\page qmlmodules.html
\title Modules

A \bold module is a collection of QML types.

To use types from a module it must be imported using the \c import statement. Successive
import statements override earlier import statements.

\section1 Importing Built-in Types

To use built-in types, you must import the module defining them.
For example, to use types from Qt, import it:

\code
import Qt 4.6
\endcode

This makes available all types in Qt that were available in Qt 4.6, regardless of the
actual version of Qt executing the QML.

Modules can be compiled-in (such as the Qt module), or they can be
defined in QML files.

\section1 Importing QML Files

To import types defined in QML files in directories relative to the file importing them,
a quoted import directory is used:

\code
import "path"
\endcode

This allows all components defined in the directory \c path to be used in
the component where this statement appears.

To import types defined in QML files that are installed somewhere on the system,
an unquoted URI is used:

\code
import com.nokia.CoolStuff 1.0
\endcode

This will access file in the directory \c com/nokia/CoolStuff/, found in some
location determined outside QML. See QmlEngine::addImportPath() and the \c -L option
to the \l {qmlviewer}{viewer} application.

The directory of installed files must include a file \c qmldir which specifies the
mapping from all type names to versioned QML files. It is a list of lines of the form:

\code
# <Comment>
<TypeName> <VersionRange> <File>
\endcode

<TypeName> is the type being made available; <VersionRange> is either a single version
number like \c 4.0 or a range of minor versions like \c 4.0-2; <File> is the (relative)
file name of the QML file defining the type.
The same type can be provided by different files in different versions.
If a type is in multiple major versions, it should be listed on a separate line.

Installed files do not need to import the module of which they are a part, as they can refer
to the other QML files in the module as relative (local) files.

Installed files \e must be referred to by version information described above,
local files \e may have it.

The versioning system ensures that a given QML file will work regardless of the version
of installed software, since a versioned import \e only imports types for that version,
leaving other identifiers available, even if the actual installed version might otherwise
use those identifiers.

\section1 Namespaces - Named Imports

When importing content it by default imports types into the global namespace.
You may choose to import the module into another namespace, either to allow identically-named
types to be referenced, or purely for readability.

To import a module into a namespace:

\code
import Qt 4.6 as TheQtLibrary
\endcode

Types from Qt 4.6 may then be used, but only by qualifying them with the namespace:

\code
TheQtLibrary.Rectangle { ... }
\endcode

Multiple modules can be imported into the same namespace in the same way that multiple
modules can be imported into the global namespace:

\code
import Qt 4.6 as Nokia
import Ovi 1.0 as Nokia
\endcode
*/

/*

See original requirement QT-558.

*/