Annotation of embedaddon/php/README.PHP4-TO-PHP5-THIN-CHANGES, revision 1.1
1.1 ! misho 1: 1. strrpos() and strripos() now use the entire string as a needle. Be aware
! 2: that the existing scripts may no longer work as you expect.
! 3:
! 4: EX :
! 5: <?php
! 6: var_dump(strrpos("ABCDEF","DEF"));
! 7: var_dump(strrpos("ABCDEF","DAF"));
! 8: ?>
! 9:
! 10: Will give you different results. The former returns 3 while the latter
! 11: returns false rather than the position of the last occurrence of 'D'.
! 12: The same applies to strripos().
! 13:
! 14: 2. Illegal use of string offsets causes E_ERROR instead of E_WARNING.
! 15:
! 16: EX :
! 17: <?php
! 18: $a = "foo";
! 19: unset($a[0][1][2]);
! 20: ?>
! 21:
! 22: Fatal error: Cannot use string offset as an array in ... on line 1
! 23:
! 24: 3. array_merge() was changed to accept only arrays. If a non-array variable is
! 25: passed, a E_WARNING will be thrown for every such parameter. Be careful
! 26: because your code may start emitting E_WARNING out of the blue.
! 27:
! 28: 4. Be careful when porting from ext/mysql to ext/mysqli. The following
! 29: functions return NULL when no more data is available in the result set
! 30: (ext/mysql's functions return FALSE).
! 31:
! 32: - mysqli_fetch_row()
! 33: - mysqli_fetch_array()
! 34: - mysqli_fetch_assoc()
! 35:
! 36: 5. PATH_TRANSLATED server variable is no longer set implicitly under
! 37: Apache2 SAPI in contrast to the situation in PHP 4, where it is set to the
! 38: same value as the SCRIPT_FILENAME server variable when it is not populated
! 39: by Apache. This change was made to comply with the CGI specification.
! 40: Please refer to bug #23610 for further information.
! 41:
! 42: 6. Starting PHP 5.0.0 the T_ML_CONSTANT constant is no longer defined by the
! 43: ext/tokenizer extension. If error_reporting is set to E_ALL notices will
! 44: be produced. Instead of T_ML_CONSTANT for /* */ the T_COMMENT constant
! 45: is used, thus both // and /* */ are resolved as the T_COMMENT constant.
! 46: However the PHPDoc style comments /** */ ,which starting PHP 5 are parsed
! 47: by PHP, are recongnized as T_DOC_COMMENT.
! 48:
! 49: 7. $_SERVER should be populated with argc and argv if variables_order
! 50: includes "S". If you have specifically configured your system to not
! 51: create $_SERVER, then of course it shouldn't be there. The change was to
! 52: always make argc and argv available in the CLI version regardless of the
! 53: variables_order setting. As in, the CLI version will now always populate
! 54: the global $argc and $argv variables.
! 55:
! 56: 8. In some cases classes must be declared before used. It only happens only
! 57: if some of the new features of PHP 5 are used. Otherwise the behaviour is
! 58: the old.
! 59: Example 1 (works with no errors):
! 60: <?php
! 61: $a = new a();
! 62: class a {
! 63: }
! 64: ?>
! 65:
! 66: Example 2 (throws an error):
! 67: <?php
! 68: $a = new a();
! 69: interface b{
! 70: }
! 71: class a implements b {
! 72: }
! 73: ?>
! 74:
! 75: Output (example 2) :
! 76: Fatal error: Class 'a' not found in /tmp/cl.php on line 2
! 77:
! 78: 9. get_class() starting PHP 5 returns the name of the class as it was
! 79: declared which may lead to problems in older scripts that rely on
! 80: the previous behaviour - the class name is lowercased. Expect the
! 81: same behaviour from get_parent_class() when applicable.
! 82: Example :
! 83: <?php
! 84: class FooBar {
! 85: }
! 86: class ExtFooBar extends FooBar{}
! 87: $a = new FooBar();
! 88: var_dump(get_class($a), get_parent_class($a));
! 89: ?>
! 90:
! 91: Output (PHP 4):
! 92: string(6) "foobar"
! 93: string(9) "extfoobar"
! 94:
! 95: Output (PHP 5):
! 96: string(6) "FooBar"
! 97: string(9) "ExtFooBar"
! 98: ----------------------------------------------------------------------
! 99: Example code that will break :
! 100: //....
! 101: function someMethod($p) {
! 102: if (get_class($p) != 'helpingclass') {
! 103: return FALSE;
! 104: }
! 105: //...
! 106: }
! 107: //...
! 108: Possible solution is to search for get_class() and get_parent_class() in
! 109: all your scripts and use strtolower().
! 110:
! 111: 10. get_class_methods() returns the names of the methods of a class as they
! 112: declared. In PHP4 the names are all lowercased.
! 113: Example code :
! 114: <?php
! 115: class Foo{
! 116: function doFoo(){}
! 117: function hasFoo(){}
! 118: }
! 119: var_dump(get_class_methods("Foo"));
! 120: ?>
! 121: Output (PHP4):
! 122: array(2) {
! 123: [0]=>
! 124: string(5) "dofoo"
! 125: [1]=>
! 126: string(6) "hasfoo"
! 127: }
! 128: Output (PHP5):
! 129: array(2) {
! 130: [0]=>
! 131: string(5) "doFoo"
! 132: [1]=>
! 133: string(6) "hasFoo"
! 134: }
! 135:
! 136: 11. Assignment $this is impossible. Starting PHP 5.0.0 $this has special
! 137: meaning in class methods and is recognized by the PHP parser. The latter
! 138: will generate a parse error when assignment to $this is found
! 139: Example code :
! 140: <?php
! 141: class Foo {
! 142: function assignNew($obj) {
! 143: $this = $obj;
! 144: }
! 145: }
! 146: $a = new Foo();
! 147: $b = new Foo();
! 148: $a->assignNew($b);
! 149: echo "I was executed\n";
! 150: ?>
! 151: Output (PHP 4):
! 152: I was executed
! 153: Output (PHP 5):
! 154: PHP Fatal error: Cannot re-assign $this in /tmp/this_ex.php on line 4
! 155:
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>