Doc #69162 [Opn->Nab]: ord() returns zero for empty string etc.

Edit report at https://bugs.php.net/bug.php?id=69162&edit=1 ID: 69162 Updated by: cmb@php.net Reported by: salsi at icosaedro dot it Summary: ord() returns zero for empty string etc. -Status: Open +Status: Not a bug Type: Documentation Problem Package: Documentation problem PHP Version: Irrelevant -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: As documented, ord() expects a string. Other types are converted to string as usual, what is documented in detail in the section "Converting to string"[1]. Passing an object to ord() results in a warning, see <https://3v4l.org/uGPeB>. Make sure to enable error reporting. [1] <http://php.net/manual/en/language.types.string.php#language.types.string.casting> Previous Comments: ------------------------------------------------------------------------ [2015-03-02 17:33:12] salsi at icosaedro dot it Description: ------------ The ord($x) function (see http://www.php.net/function.ord) returns zero for the empty string or anything that can be silently converted to the empty string (NULL, TRUE). Surprisingly, ord($x) also returns 0 if an object is passed, although echo new stdClass() raises E_RECOVERABLE_ERROR: Object of class stdClass could not be converted to string. Either the documentation should state this, or the engine should raise an error, just like it already does when $x is array or resource. I run into this issue while reading the value of a byte read from a file: ord(fread($f,1)) returned 0 on EOF causing a infinite loop. An error would have helped detecting this bug early. Test script: --------------- // unexpected: echo "ord(false): "; var_dump(ord(false)); // int(0) (!) echo "ord(null): "; var_dump(ord(null)); // int(0) (!) echo "ord(''): "; var_dump(ord('')); // int(0) (!) echo "ord(new stdClass()): "; var_dump(new stdClass()); // int(0) (!) // more or less expected: echo "ord(true): "; var_dump(ord(true)); // int(49) echo "ord(123): "; var_dump(ord(123)); // int(49) echo "ord(0): "; var_dump(ord(0)); // int(48) echo "ord(-1): "; var_dump(ord(-1)); // int(45) echo "ord(3.14): "; var_dump(ord(3.14)); // int(51) echo "ord(0.0): "; var_dump(ord(0.0)); // int(48) echo "ord(-1.0): "; var_dump(ord(-1.0)); // int(45) //echo "ord(array()): "; var_dump(ord(array())); // E_WARNING: ord() expects parameter 1 to be string, array given //echo "ord(array(1,2,3)): "; var_dump(ord(array(1,2,3))); // E_WARNING: ord() expects parameter 1 to be string, array given //echo "ord(fopen(__FILE__, 'r')): "; var_dump(ord(fopen(__FILE__, 'r'))); // E_WARNING: ord() expects parameter 1 to be string, resource given Expected result: ---------------- // possible alternative: echo "ord(false): "; var_dump(ord(false)); // E_WARNING: empty string in ord() echo "ord(null): "; var_dump(ord(null)); // E_WARNING: empty string in ord() echo "ord(''): "; var_dump(ord('')); // E_WARNING: empty string in ord() echo "ord(new stdClass()): "; var_dump(new stdClass()); // E_RECOVERABLE_ERROR: Object of class stdClass could not be converted to string // more or less expected: ... ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=69162&edit=1