On 5 Sep 2011, at 15:51, Raffael Cavallaro wrote:
On Sep 5, 2011, at 10:02 AM, Steve Graham wrote:
Can someone help?
Marc's reply is, of course, succinct and correct.
If you want a fuller understanding of scope, I've found the wikipedia article to be relatively clear and to the point: <http://en.wikipedia.org/wiki/Scope_(computer_science)>
It covers both lexical (a.k.a. "static") scope, and dynamic scope, and gives examples.
If you've got a C language kind of background, to a reasonable approximation, dynamic scoping is a lot like a global variable: anyone who reads or writes a given binding sees the same one. It caries similar risks to a global variable, but there are also some handy things you can do with them such as set up exception handlers. Static / lexical scoping is like the normal local variables in a function. Hope that helps (and that if it's nonsense someone will correct me). Cheers, B -- benjohn@fysh.org - Twitter @benjohnbarnes - Skype benjohnbarnes - Mobile +44 (0) 7968 851 636