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Select Float - Both A and B are evaluated?

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    Select Float - Both A and B are evaluated?

    Given this in an empty new project, in the level blueprint :

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    I get a Divide by zero warning in the log, which means both A and B were evaluated, whereas only A should have been (or so would seem logical to me, at least).

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    An actual situation where MyArray == 1 :

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    It returns the divide by zero warning, but it shouldn't?

    It's not a critical issue, but imagining A and/or B having a complex calculation, it seems like a waste of resources having both being evaluated if only one is necessary?

    Is that intended or should it be reported as a bug?
    Attached Files

    #2
    Looking at the source code:

    float UKismetMathLibrary::SelectFloat(float A, float B, bool bSelectA)
    {
    return bSelectA ? A : B;
    }

    To call this function, you have to send float A, float B, and the bSelectA, and then it returns the result. To send float A and B into the function, you must first evaluate them. So yes, this should be happening.

    Comment


      #3
      A compiler doesn't know if only one is needed.
      Your "select" boolean can be true or false at runtime.

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