Req #68126 [NEW]: syntax for optional definition of function return type

From: lefevre dot 10 at osu dot edu Operating system: Linux PHP version: 5.6.0 Package: PHP Language Specification Bug Type: Feature/Change Request Bug description:syntax for optional definition of function return type Description: ------------ It would be useful to optionally be able define a return type for a function, perhaps like so: function foo($arg1, $arg2) returns array { ... } Currently the Code by Contract principle is not fully implementable in interfaces because there is no way to guarantee a return type for functions, or even any return value at all. Adding a return type would allow one to do better code by contract: interface iMyInterface { function handle_data($arg1) returns iMyResponse; } interface iMyResponse { ... } When writing code that implements or depends on iMyInterface, I can know what type I will be getting out of the handle_data method. Optionally one could specify multiple return types: function my_string_function($string) returns string, boolean {...} As the author of the function, I will know if I have a logic error when this function I've written doesn't return the pre-defined types and I get an error. As a client programer (who will later use the above function, but hasn't written it), I will know at a glance what output I can expect from a function, without scanning through the body to deduce it. For backwards compatibility, flexibility and php-ishness, I don't think this should be required, but optional. function my_string_function_1() {...} function my_string_function_2() returns string, boolean {...} function my_string_function_3() returns string, boolean, array {...} Test script: --------------- <?php function my_string_function($string) returns array, string, boolean { // do nothing; syntax presently invalid. } -- Edit bug report at https://bugs.php.net/bug.php?id=68126&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=68126&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=68126&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=68126&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=68126&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=68126&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=68126&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=68126&r=needscript Try newer version: https://bugs.php.net/fix.php?id=68126&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=68126&r=support Expected behavior: https://bugs.php.net/fix.php?id=68126&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=68126&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=68126&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=68126&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=68126&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=68126&r=dst IIS Stability: https://bugs.php.net/fix.php?id=68126&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=68126&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=68126&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=68126&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=68126&r=mysqlcfg