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Resolving the wrong function at compile time BUG?

I am using Visual Studio 2012 Update 1 and .NET 4.5 code here.

void Test(Action a) { }
void Test(Func<int> a) { }
void TestError()
{
    bool throwException = true;
    //Resolves to Test(Action a)
    Test(() =>
    {
    });
    //Resolves to Test(Action a)
    Test(() =>
    {
        if (throwException) throw new Exception();
    });
    //Resolves to Test(Func<int> a)
    //(This seems like a bug since there is no return value)
    Test(() =>
    {
        throw new Exception();
    });
    //Resolves to Test(Action a)
    //(With warning unreachable code detected)
    Test(() =>
    {
        throw new Exception();
        return; //unreachable code detected
    });
}

It looks like the last function call resolves Func instead of Action incorrectly and has something to do with unconditional exception throwing.

Is this a mistake? Thank.

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1 answer

Well, it seems reasonable to me that both are valid candidates. In other words, I believe that for the conversion of () => { throw new Exception(); }both Func<int>, it Actionmakes sense to convert () => { throw new Exception(); }. In both cases, the end of the method is unavailable - it would be fair to put it in a normal named method as follows:

public int GoBang()
{
    throw new Exception();
}

and then write:

Func<int> foo = GoBang;

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7.5.3.3 ( ) :

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  • [...]

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, Func<int> Action... .

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