Fwd: [PHP-DEV] * New Parameter Parsing Functions *

Guys, Andrei sent this Email a while ago and I don't remember anyone giving feedback. We'd be happy to hear what people think about this new parameter API in the Zend Engine. I think it has good potential especially for simplifying functions which accept read-only arguments (which is the case for most functions) of pre-determined types. Please take another look at what Andrei wrote and see what you think. Andi

Date: Tue, 10 Jul 2001 10:35:04 -0500 From: Andrei Zmievski <andrei@ispi.net> To: PHP Developers <php-dev@lists.php.net> User-Agent: Mutt/1.2.5i Subject: [PHP-DEV] * New Parameter Parsing Functions * New parameter parsing functions =============================== It should be easier to parse input parameters to an extension function. Hence, borrowing from Python's example, there are now a set of functions that given the string of type specifiers, can parse the input parameters and store the results in the user specified variables. This avoids most of the IS_* checks and convert_to_* conversions. The functions also check for the appropriate number of parameters, and try to output meaningful error messages. Prototypes ---------- /* Implemented. */ zend_parse_parameters(int num_args, char *type_spec, ...); zend_parse_parameters_ex(int flags, int num_args, char *type_spec, ...); /* Not implemented yet. */ zend_parse_parameters_hash(HashTable *ht, char *type_spec, ...); zend_parse_parameters_hash_ex(int flags, HashTable *ht, char *type_spec, ...); The zend_parse_parameters() function takes the number of parameters passed to the extension function, the type specifier string, and the list of pointers to variables to store the results in. The _ex() version also takes 'flags' argument -- current only ZEND_PARSE_PARAMS_QUIET can be used as 'flags' to specify that the function should operate quietly and not output any error messages. The auto-conversions are performed as necessary. Arrays, objects, and resources cannot be autoconverted. Type specifiers ---------------

 l      - long
 d      - double
 s      - string (with possible null bytes) and its length
 b      - boolean, stored in zend_bool
 r      - resource (stored in zval)
 a      - array
 o      - object (of any type)
 O      - object (of specific type, specified by class entry)
 z      - the actual zval

The following characters also have a meaning in the specifier string:

     | - indicates that the remaining parameters are optional, they
                should be initialized to default values by the extension since they
                will not be touched by the parsing function if they are not
                passed to it.
        / - use SEPARATE_ZVAL_IF_NOT_REF() on the parameter it follows
        ! - the parameter it follows can be of specified type or NULL (only applies
             to 'a', 'o', 'O', 'r', and 'z'). If NULL is passed, the results
                pointer is set to NULL as well.

Examples -------- /* Gets a long, a string and its length, and a zval */ long l; char *s; int s_len; zval *param; zend_parse_parameters(ZEND_NUM_ARGS(), "lsz", &l, &s, &s_len, &param); /* Gets an object of class specified by my_ce, and an optional double. */ zval *obj; double d = 0.5; zend_parse_parameters(ZEND_NUM_ARGS(), "O|d", &obj, my_ce, &d); /* Gets an object or null, and an array. If null is passed for object, obj will be set to NULL. */ zval *obj; zval *arr; zend_parse_parameters(ZEND_NUM_ARGS(), "O!a", &obj, &arr); /* Gets a separated array. */ zval *arr; zend_parse_parameters(ZEND_NUM_ARGS(), "a/", &arr)); /* Get only the first three parameters (useful for varargs functions). */ zval *z; zend_bool b; zval *r; zend_parse_parameters(2, "zbr!", &z, &b, &r); /* Get either a set of 3 longs or a string. */ long l1, l2, l3; char *s; if (zend_parse_parameters_ex(ZEND_PARSE_PARAMS_QUIET, ZEND_NUM_ARGS(), "lll", &l1, &l2, &l3)) {

        /* manipulate longs */
} else if (zend_parse_parameters_ex(ZEND_PARSE_PARAMS_QUIET, ZEND_NUM_ARGS(), "s", &s)) {
        /* manipulate string */

} else {

        /* output error */

} Comments and feedback are welcome. -Andrei * If it's never finished, you can't prove it doesn't work. * -- PHP Development Mailing List <http://www.php.net/> To unsubscribe, e-mail: php-dev-unsubscribe@lists.php.net For additional commands, e-mail: php-dev-help@lists.php.net To contact the list administrators, e-mail: php-list-admin@lists.php.net