Re: question(s) about declaring variables

"MikeD" <nobody@xxxxxxxxxxx> wrote in message
news:%23eokBo2eFHA.1136@xxxxxxxxxxxxxxxxxxxxxxx
> I have to question that. Any performance hit would indeed be minimal (if
> existant, or at least measureable, at all), but I don't think they'd
> compile exactly the same. It's two different things. One is type-casting a
> literal value to a specific data type and this occurs at compile time.
> Another is *converting* a literal value from one data type to a different
> data type and this occurs at runtime (and subsequently happens every time
> the code is executed).

The compiler must optimise it.

> I really think you're mistaken. I don't see how they can compile
> identically.

I found a little trick a few years ago, if the compiler finds 2 functions
are exactly the same it optimises out one of the functions. You can check it
has done this by finding the address of each function using the AddressOf
operator. If the 2 functions are identical they will have the same address
once fully compiled. Give it a try. When in the IDE the functions have
different addresses but once compiled they have the same address

Put this code in a module

Public Function A(ByVal X as Long) as Long
A = X * 1000&
End Function

Public Function B(ByVal Y as Long) as Long
B= X * CLng(1000)
End Function

And this code in a form:

private sub Form_Load()
Me.Caption = AddOf(AddressOf A) & " " & AddOf(AddressOf B)
End Sub

Private Function AddOf(ByVal Address as Long) as Long
AddOf = Address
End Function





>
> --
> Mike
> Microsoft MVP Visual Basic
>
>


.

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