Re: Re: Question about superglobals

Sam Barrow wrote: > You say that superglobals were not designed to be user defined, think > about it, the concept of a superglobal is present in C and C++, two of > the maturest and strictest languages around. The concept of having to declare your globals is unique to PHP, true. It is one of the oldest features in PHP too. So, a little history... Back in 1989 I spent at least a month chasing a bug at a company in Canada called Bell Northern Research. It was a weird crash bug in a rather complicated system. It was mostly written in C and after pouring through reams and reams of code printouts day after day, I finally found that it was due to a side effect of some obscure function overwriting a global variable that was used in a completely different area of the code. That particular feature of the C language was not popular with me for a long time after that, and when it came time to work out function scoping of variables in PHP, I made sure to not make that same mistake. And yes, because PHP is a web language and there are common aspects of a web request that many functions will need to act on, it makes sense to have a finite number of clearly labeled global arrays like _GET, _POST, etc. And later on, being able to access any global via $_GLOBALS was added, but again, it is a very descriptive name and not likely to result in someone mistaking it for something else and ending up with strange side effects. I am definitely not in favor of destroying what I consider a rather good design decision just to avoid a couple of keystrokes here and there. So yes, you will have to keep adding "global $cfg;" to your functions, or accessing it via $_GLOBALS['cfg'], and when you forget, it won't work. And yes, you will grumble a bit at that, but that is nothing compared to trying to find a bug caused by a global side effect in someone else's code. Trust me, you will grumble a lot more at that. -Rasmus