Req #62519 [Opn]: Find out about a function's call context

Edit report at https://bugs.php.net/bug.php?id=62519&edit=1 ID: 62519 User updated by: awilliams at linkme dot com dot au Reported by: awilliams at linkme dot com dot au Summary: Find out about a function's call context Status: Open Type: Feature/Change Request Package: Unknown/Other Function Operating System: any PHP Version: Irrelevant Block user comment: N Private report: N New Comment: I would like to present a more concrete example of why I think this would be an elegant solution to a coding dilemma I have. I wrote a couple of functions to generate html for <select> mark-up from mySql tables and php arrays. Some times I want to call them directly and I want then to output the html, other times I want to use them in string expressions, in which case I want them to return the html. As it stands I would have to do this using different function names, which looks messy. To implement this I have two choices, maintain two separate functions doing almost the same thing. That is never best practice. Sooner or later you forget to do a change to both of them. Declare the string returning function and call it from the string printing version. This is wasteful of stack and call time resources, I try not to code like that. I am left looking at this thinking it would be a really elegant solution if the function its self could tell what context it was called in and either echo or return the output as required. I agree that it’s a somewhat unconventional suggestion. I wouldn't expect it of 'C'. I write in PHP because many things are simpler an more flexible here, and this would definitely add a new form of flexibility that I have a use for. Thank you and that's my last word on it. Alan Previous Comments: ------------------------------------------------------------------------ [2012-07-10 14:01:11] nikic@php.net PHP is a dynamically typed language. It can't in the general case know what type is expected. Simple example if f1() + f2(). Here int, float and array would be viable return types. Whether the return value is used or not is known to the engine and also exposed to internal functions. But I don't think that it makes sense to expose it to userland functions. Functions shouldn't behave different based on whether the return value is used or not. ------------------------------------------------------------------------ [2012-07-10 04:10:55] awilliams at linkme dot com dot au Description: ------------ I would like to be able to tell if a function was called from a context that is expecting a return value or not. Additionally what type is expected. eg('hello'); // called not expecting a return value echo eg('hello').' world'; // called expecting a string function eg($s) { if(return){ // suggested overloading of the return keyword to report the function context. return ($s); } else{ echo $s; } } Additionally gettype(return); and is_string(return); is_array(return); etc ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=62519&edit=1