PHP 4.0 Bug #9979 Updated: (! $a == $b) and ($a != $b) discreprency

ID: 9979 Updated by: elixer Reported By: ying@zippydesign.com Old-Status: Open Status: Feedback Bug Type: Scripting Engine problem Assigned To: Comments: Looking at http://www.php.net/manual/en/language.operators.precedence.php I see that the comparison operators have lower precendence than the negation operator, so in essence you are saying that the following two expressions should be equivalent: (!$a) == $b $a != $b Is that correct? Sean Previous Comments: --------------------------------------------------------------------------- [2001-03-25 13:40:25] ying@zippydesign.com I've noticed a difference in how (! $a == $b) and ($a != $b) behaves between in PHP 4.04pl1. I think those should be syntactically equivalent, but with PHP 4.04pl1 they are not, whereas with older versions they are. Here is a script to test this: <? $a = "foo"; $b = "bar"; echo "nTest 1: "; echo (! $a == $b) ? "true" : "false"; echo "nTest 2: "; echo ($a != $b) ? "true" : "false"; echo "n"; ?> With PHP4.04pl1 the results are: Test 1: false Test 2: true With PHP3.18 the results are: Test 1: true Test 2: true It would seem that the results with PHP 4 are wrong here, please advise. Information about my system follows: OS: Redhat Linux Kernel: 2.4.1 PHP Version: 4.04pl1 './configure' '--disable-debug' '--with-config-file-path=/usr/local/etc' '--enable-bcmath' '--with-mysql' '--with-pgsql' '--with-gdbm' '--with-openssl' '--with-curl' '--with-readline' '--enable-inline-optimization' PHP Version: 3.18 ./configure '--disable-debug' '--enable-force-cgi-redirect' '--enable-track-vars' '--with-config-file-path=/etc/httpd/conf' '--enable-sysvsem' '--enable-sysvshm' '--with-mysql' I am using the standard php ini files (php.ini-dist and php3.ini-dist) with no changes in both tests. Please advise. --------------------------------------------------------------------------- ATTENTION! Do NOT reply to this email! To reply, use the web interface found at http://bugs.php.net/?id=9979&edit=2