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/*!
    \previouspage Project
    \nextpage PropertyOptions
    \qmltype Properties
    \inqmlmodule QbsLanguageItems
    \ingroup list-of-items
    \keyword QML.Properties

    \brief Provides conditional setting of properties.

    \note This topic documents the Properties item in the context of \l{Product}
    {products}. For more information about using it in sub-projects, see
    \l{SubProject}.

    The Properties item is an auxiliary item for setting multiple property values conditionally.

    In the following example, two properties are set if the project is built for Windows:
    \code
    Product {
        Properties {
            condition: qbs.targetOS.includes("windows")
            cpp.defines: ["ON_WINDOWS"]
            cpp.includePaths: ["extraWindowsIncludes"]
        }
    }
    \endcode

    As the above example demonstrates, the \c Properties item is especially useful if there are
    several properties whose values depend on the same set of conditions.
    These conditions do not need to be mutually exclusive, but care should be taken not to set
    the same scalar property in more than one matching \c Properties item. \QBS makes no guarantees
    about the value of the property in such cases.

    If the same property is set both inside and outside of a \c Properties
    item, the behavior depends on the type of property:
    \list
    \li For scalar values, the outside binding is only considered if none of the \c Properties
        conditions match, that is, it acts as an "else" case.
    \li For list values, the outside value is always considered.
    \endlist
    \code
    Product {
        Properties {
            condition: qbs.targetOS.includes("windows")
            cpp.defines: ["ON_WINDOWS"]
            cpp.includePaths: ["myWindowsIncludes"]
            cpp.treatWarningsAsErrors: false
        }
        Properties {
            condition: qbs.targetOS.includes("linux")
            cpp.defines: ["ON_LINUX"]
            cpp.includePaths: ["myLinuxIncludes"]
        }
        cpp.defines: ["ALL_PLATFORMS"]
        cpp.treatWarningsAsErrors: true
    }
    \endcode
    is roughly equivalent to
    \code
    Product {
        cpp.defines: {
            var defines = ["ALL_PLATFORMS"];
            if (qbs.targetOS.includes("windows"))
                defines.push("ON_WINDOWS");
            if (qbs.targetOS.includes("linux"))
                defines.push("ON_LINUX");
            return defines;
        }
        cpp.includePaths: {
            if (qbs.targetOS.includes("windows"))
                return ["myWindowsIncludes"];
            if (qbs.targetOS.includes("linux"))
                return ["myLinuxIncludes"];
            return base ? base : original;
        }
        cpp.treatWarningsAsErrors: !qbs.targetOS.includes("windows")
    }
    \endcode

    In Properties items, one can access the \l{Special Property Values#outer}{outer} value of a
    property.
    \code
    Product {
        property string theFeature: "basic"
        Properties {
            condition: qbs.targetOS.includes("windows")
            theFeature: outer + "_plus_windows" // === "basic_plus_windows"
        }
        Properties {
            condition: qbs.targetOS.includes("linux")
            theFeature: outer + "_plus_linux"   // === "basic_plus_linux"
        }
        cpp.defines: 'THE_FEATURE="' + theFeature + '"'
    }
    \endcode

*/

/*!
    \qmlproperty bool Properties::condition

    The condition to be used for the other bindings in this item.

    \default true
    \note The special value \c undefined can be used to indicate
          that this condition should be considered true if and only if none of the other
          Properties items matched for a given property binding.
*/

/*!
    \qmlproperty bool Properties::overrideListProperties

    List properties set within this item will override the values coming from
    modules, rather than getting merged with them, which is the default behavior.
    Use this in the rare case that a module you depend on inserts a value into
    a list property that is problematic for some product.

    \defaultvalue \c false
*/
