Recursion Depths Errors

Maximum Statement Or Expression Depth Exceeded

What happened?

A QML statement or expression was too deeply nested for the compiler. This usually only happens for generated code where statements or expressions can be very long, as the recursion limit is usually large enough for any sensible QML document.

Why is this bad?

The QML engine will not be able to run this code.

Example

import QtQuick

Item {
    function f() {
        let x = 1 + 1 + .... + 1 // maximum depth exceeded: add too many ones together
        return x
    }

    Item { Item { .... } } // maximum depth exceeded: too many nested Item's
}

You can fix this warning by auto-generating smaller code pieces. You could split deeply nested Components in multiple files or inline components, or split deeply nested expressions into multiple expressions:

import QtQuick

Item {
    function f() {
        let x = 1 + 1 + .... + 1 // first half of the split
        x += 1 + 1 + .... + 1 // second half of the split
        return x
    }

    component NestedItem : Item { Item {... }} // first half of the nested Item
    component DeeplyNestedItem: Item { ... NestedItem{} ... } // second half of the nested Items + NestedItem
    DeeplyNestedItem {}
}

© 2024 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.