Hello,
I was just inspecting/debugging my latest/newest video codec hehehehehe
and
I encountered this line where I was trying to be smart and efficient and
look what it brought me !
It brought me a bug, a very funny bug too, first I didn't see it, it took
a
few seconds which I rare and then I realized what is going on:
First I let you play with this line for a few seconds, can you see what's
the problem ?
if (vComponentsRemaining * 10 + vComponentsCompressed * 2) and 7 > 0 then
//
mod 8
Ok I let you be for a few seconds, take a look again, until you absolutely
sure what the problem is.
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Ok,
Now I tell you what I think the problem is:
Delphi knows two kinds of "and"'s:
A logical "and"
and
A bitwise "and"
So Delphi is interpreting what I wrote wrongly.
How funny is that ?
It wouldn't have happened if I used mod or simply brackets.
Now I shall fix the code:
if ((vComponentsRemaining * 10 + vComponentsCompressed * 2) and 7) > 0
then
// mod 8
See I LOVE BRACKETS, always use brackets is best !
I believe this is actually a small, little, but dangerous weakness in the
Delphi language.
Maybe a little fix is better:
LogicAnd
BitwiseAnd
Yeah.
Oh well.
Bye,
Skybuck.
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