u increment after! asigning, so far so good, but for math reasons the
interpreter has to keep in mind the 123 you want to assign before increment
to the same var.

this is absolutely correct what php does here.

$num = ++$num; would print 124
the same like

on the other hand this is just bullshit I would release any programmer using
that type of code.


<clanc...@cybec.com.au> wrote in message
> Daevid Vincent is surprised that:
> $num = 123;
> $num = $num++;
> print $num;  //this prints 123 and not 124 ?!!
> To me this is relatively logical. As I understand it, the post-increment
operator says "do
> something with the variable, and then increment it. The trouble in this
case is that we
> are doing something irrational; we are copying the number back to itself,
and to me it is
> reasonably logical (or at least no less illogical than the alternative) to
assume that if
> we copy it to itself, then increment the original version, the copy will
not be
> incremented.
> However there is one feature of PHP which, to my mind, is really bad
design. How many of
> you can see anything wrong with the following procedure to search a list
of names for a
> particular name?
> $i = 0; $j = count ($names); while ($i < $j)
> { if ($names[$i] == $target) { break; }
> ++$i;
> }
> As long as the names are conventional names, this procedure is probably
safe to use.
> However if you allow the names to be general alphanumeric strings, it is
not reliable. One
> of my programs recently broke down in one particular case, and when I
eventually isolated
> the bug I discovered that it was matching '2260' to '226E1'. (The logic of
this is: 226E1
> = 226*10^1 = 2260).
> I agree that I was well aware of this trap, and that I should not have
used a simple
> comparison, but it seems to me to be a bizarre design decision to assume
that anything
> which can be converted to an integer, using any of the available
notations, is in fact an
> integer, rather than making the default to simply treat it as a string. It
is also a trap
> that it is very easy to fall into if you start off thinking about simple
names, and then
> extend (or borrow) the procedure to use more general strings.
> And can anyone tell me whether, in the above case, it is sufficient to
write simply:
>     if ((string) $names[$i] == $target),
> or should I write:
>     if ((string) $names[$i] == (string) $target)?
> (I decided to play safe and use strcmp ().)

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