Bug #18480 Updated: Undocumented global use

ID: 18480 Updated by: sniper@php.net Reported By: seb@delahaye.net -Status: Open +Status: Closed Bug Type: Documentation problem Operating System: all PHP Version: 4.2.1 Previous Comments: ------------------------------------------------------------------------ [2002-07-23 10:40:46] cynic@php.net gosh, and how would the KeepVariables() function know to access the *global* variables $a and $b if you didn't tell it to? this is IMO just a matter of common sense, so please, stop this thread. ------------------------------------------------------------------------ [2002-07-23 10:27:56] seb@delahaye.net Yes. I knew I had to declare the var as global is the function where I wanted to use it. What was not clear for me was that I needed to declare it as global in the two functions. If I take the functions from the patch as example, declaring $a and $b as global in Sum() was evident, but declaring them as global also in KeepVariables() was not evident. Of course, when you *know* it, it's clear, but when you don't know it, and since the doc isn't IMHO clear about this, it's not evident at all. This patch should be more clear (hopefully): Index: en/language/variables.xml =================================================================== RCS file: /repository/phpdoc/en/language/variables.xml,v retrieving revision 1.52 diff -u -r1.52 variables.xml --- en/language/variables.xml 3 Jul 2002 22:51:23 -0000 1.52 +++ en/language/variables.xml 23 Jul 2002 14:26:36 -0000 @@ -375,8 +375,10 @@ The above script will output &quot;3&quot;. By declaring <varname>$a</varname> and <varname>$b</varname> global within the function, all references to either variable will refer to the - global version. There is no limit to the number of global - variables that can be manipulated by a function. + global version. In the same way, if you want to access in a function + to a var from another function, declare it as global in both functions. + There is no limit to the number of global variables that can be + manipulated by a function. </simpara> <simpara> ------------------------------------------------------------------------ [2002-07-22 19:05:35] rasmus@php.net I really don't understand why this point would have confused you. The only variables you can access inside a function are the variables local to that specific function. If you want to access a variable defined outside of the function (ie. a global) you have to specify you want to access that global variable. There is no way for a function to access another function's locally scoped variables. ------------------------------------------------------------------------ [2002-07-22 19:00:11] seb@delahaye.net For me, the fact that it was needed to create a global variable in one function to access to in another was not clear. Specially because it's not the case for vars that are outside any function. I don't think it's something evident. My patch probably doesn't explain it well, I'll try to make one more clear tomorrow (yup, it's damn too late here). ------------------------------------------------------------------------ [2002-07-22 18:54:14] rasmus@php.net That's not a different use though. You are simply creating a global variable in one function and accessing it in another. I don't think this patch clarifies anything. Perhaps the fact that you can create global variables inside a function is not documented well enough, but a much simpler documentation fix can take care of that. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/18480 -- Edit this bug report at http://bugs.php.net/?id=18480&edit=1