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switch may fall through (no it may not)


switch may fall through (no it may not)

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switch may fall through (no it may not)
Tag : cpp , By : Alex Sadzawka
Date : January 11 2021, 03:32 PM

I wish did fix the issue. Consider fun(static_cast(42)). This is a perfectly well-defined conversion, but the function from your question will reach the end without returning, and your program's behavior will be undefined. That's why GCC warns that control may reach the end of a non-void function.
So why not add a default case? Consider what happens if someone goes back and adds another constant to E, but forgets to update fun. Without a default, GCC will helpfully warn you that the switch doesn't handle all of E's constants. If you add a default case, you've defeated that very helpful protection.
enum class E {a, b, c};

QVariant fun(E e) {
     switch (e) {
        case E::a: return "something";
        case E::b: return "something_else";
        case E::c: return "something_different";
    }
    return "some_default"; // or throw or abort()
}

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What's the best way to document intentional switch fall-through?


Tag : php , By : Theo
Date : March 29 2020, 07:55 AM
around this issue Although the question explicitly asks about phpDoc, here's an IDE-specific solution for PHPStorm.
For Javascript, comment
//noinspection FallthroughInSwitchStatementJS
/** @noinspection PhpMissingBreakStatementInspection */

switch fall through being ignored by JSHint


Tag : javascript , By : dnyaneshwar
Date : March 29 2020, 07:55 AM
this will help JSHint seems to expect the comment to be on the line right before the case.
// Example
/* falls through */
case Major === 0 && Minor === 0 && Patch < 442:
    console.log('test');
// You can tell JSHint that you don't use break intentionally by
// adding a comment /* falls through */ on a line just before
// the next `case`.

Is there a VB .NET equivalent to C Fall Through switch?


Tag : c , By : changke
Date : March 29 2020, 07:55 AM
seems to work fine Your premise is wrong. In C# you can't fall through to the next case if the current case has statements. Trying to do so will result in a compilation error.
You can, however, (ab)use goto case to get this working.
switch(0)
{
    case 0:
        Console.WriteLine("0");
        goto case 1;
    case 1:
        Console.WriteLine("1");
        break;

}

Switch statement does not seem to fall through


Tag : javascript , By : JulianCT
Date : March 29 2020, 07:55 AM
will be helpful for those in need You cannot use location: 'Leon, Spain', + woeid: '', together. In order to identify a location you can use a valid field, in your case location.
$.simpleWeather({
    location: 'Leon, Spain',
    unit: 'f',
    success: function(weather) {
        console.log('weather.code is: ' + weather.code);
        switch(weather.code) {
            case '27':
                conditionsImageClass = '.diw-clouds:before';
                break;
            case '28':
                conditionsImageClass = '.diw-clouds-moon:before';
                break;
            default:
                conditionsImageClass = '.test'
                break;
        }
        console.log('conditionsImageClass is: ' + conditionsImageClass);
    },
    error: function(error) {
        console.log('Error: ' + error);
    }
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery.simpleWeather/3.1.0/jquery.simpleWeather.min.js"></script>

Making use of a fall-through switch


Tag : php , By : Derek
Date : March 29 2020, 07:55 AM
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