function-used-before-declaration.qdoc

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// Copyright (C) 2026 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
/*!
\page qmllint-warnings-and-errors-function-used-before-declaration.html
\ingroup qmllint-warnings-and-errors
 
\title Function used before its declaration
\brief [function-used-before-declaration] A function was used before its declaration.
 
\qmllintwarningcategory function-used-before-declaration
 
This category is disabled by default.
 
\section1 Function usage before its declaration
 
\section2 What happened?
You called a function or used its name before the function was declared.
 
\section2 Why is that bad?
It makes the code more difficult to read and may cause confusion.
 
Note that the function is made available before its declaration due to
\l{https://developer.mozilla.org/en-US/docs/Glossary/Hoisting}{hoisting}.
 
\section2 Example
\qml
import QtQuick
 
Item {
    function f() {
        g(42)
        function g() { return 42; }
    }
}
\endqml
 
To fix this warning, move the declaration before the usage.
 
\qml
import QtQuick
 
Item {
    function f() {
        function g() { return 42; }
        g(42)
    }
}
\endqml
*/