Re: Variable Scope

How about allowing for metaPasses within the castle? Am sure this topic came up, what's the conclusion? Philip On Thu, 18 Jan 2001, Rasmus Lerdorf wrote: > > I'm a bit troubled with the fact that variables declared at the top of your > > script are not then global to functions within that script. That in order > > to see that variable within a function you'd have to declare it as global in > > the function (understanding that the variable could have been set at the top > > of the script). This seems extremely backwards to me (me being a VB guy). > > > > Would someone kindly shine the light down upon me with an explanation of > > this logic? And why can't I possibly declare the variable as Global at the > > top of my script? > > Once upon a time in a cold land far far away, a brave programming team was > building a castle. The castle was large and complex with countless rooms > and secret passageways. On one frightful day the team got stuck. They > had built one too many rooms with one too many secret passageways and > suddenly the castle was beginning to crumble. A desperate plea went out > to the local wizard who was strong and powerful. The local wizard looked > at the problem, saw the many rooms and the many secret passageways and > gave the following decree: "Thou must post a sign in each and every room > declaring which secret passageways connect to this room." The brave > programming team feared the wizard and implemented the decree immediately > although they really didn't understand how it would help. What they found > was that a number of secret passageways did not connect to anything and > others connected to places that didn't make any sense. After fixing these > the castle was solid again. > > The moral of this tale is that one must declare ones' global variables > that one intends to use within a function. In languages like C where this > is not required one can end up with all sorts of weird side effects when a > function changes a variable that the programmer intended to be local to > the function and it affects code elsewhere in the system. This is almost > impossible to track down. The tale of the brave programming team led to > this being a requirement in PHP. > > -Rasmus > > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, e-mail: php-general-unsubscribe@lists.php.net > For additional commands, e-mail: php-general-help@lists.php.net > To contact the list administrators, e-mail: php-list-admin@lists.php.net >