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  1. Qt
  2. QTBUG-98195

Default function arguments have the wrong scope

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    Description

      In ECMAScript, default function arguments are placed in their own environment record, which then acts as the parent scope for the function body. That means that

      console.log((function() {
        let a = 1;
        function f(fn = function(){ return a; }){ const a = 2; return fn() }
        return f();
    })())

      should print 1. However, in QML, it will print 2 because fn ends up in the scope of f's body, and thus uses the a from there instead of from the outer scope.

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          relates to

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-104751 Can't have type annotations and default arguments

          • P3: Somewhat important - Should be fixed, but doesn't affect the release in any way.
          • Open
          resulted from

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-98032 QML/Javascript: Using an anonymous function as a default parameter in a function signature crashes the application.

          • P1: Critical - Urgent and Important, will STOP the release if matched with set FixVersion field. This includes regressions from the last version that are not edge cases; Data loss; Build issues; All but the most unlikely crashes/lockups/hanging; Serious usability issues and embarrassing bugs & Bugs critical to a deliverable. This is the highest possible priority for requirements.
          • Closed
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              qtqmlteam Qt Qml Team User
              fabiankosmale Fabian Kosmale
              Vladimir Minenko Vladimir Minenko
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                Created:
                Updated:

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