RE: [PHP] Whacky increment/assignment logic with $foo++ vs ++$foo

At 1:59 PM +0100 10/7/09, Ashley Sheridan wrote:

On Wed, 2009-10-07 at 08:54 -0400, tedd wrote: At 6:15 PM -0700 10/6/09, Daevid Vincent wrote:

Except that: $a = 123; $b = $a++; echo $b; //gives 123, not 124 as you logically expect it to and common sense would dictate, regardless of what K&R or anyone else says.

That's not the way I look at it.

    $b = $a++;

means to me "take the value of $a and assign to $b and then increment $a." Whereas:

    $b = ++$a;

means to me "increment $a and take the value of $a and assign to $b." Cheers, tedd

Which is exactly the reason for the two operators in C. Thanks, Ash

Ash: The reason was simply to provide a different way of doing something. For example, take the statements of: $a = 10; $b = a$++; // $b = 10 and $a = 11 This post-increment operator was a way to assign 10 to $b and increment $a in one statement. Whereas: $a = 10; $b = ++a$; // $b = 11 and $a = 11 This pre-increment operator was a way to increment $a and also assign that value to $b. Both are perfectly valid ways of using the operator. Also realize that the pre-decrement and post-decrement operators worked in similar fashion. Now why would someone want to do that? There could be many reasons, but that was left to the programmer to use as he/she needed. However, what I find wacky about all of this is: for($i=1; $i<=10; $i++)

    {
    echo($i);
    }

and for($i=1; $i<=10; ++$i)

    {
    echo($i);
    }

Do exactly the same thing. I would have expected the first to print 1-10, while the second to print 2-10, but they both print 1-10. Cheers, tedd -- ------- http://sperling.com http://ancientstones.com http://earthstones.com