[XQuery Talk Mailing List Archive Home] [By Date] [By Thread] [By Subject] [By Author] [Recent Entries] [Reply To This Message]

Setting global variables

Ronald Bourret rpbourret at rpbourret.com
Wed Oct 31 12:26:01 PST 2007


  Setting global variables

Michael Kay wrote:

> Sounds like you're having difficulty getting procedural programming out of
> your mindset... It's this concept of "later" that gives it away. In
> functional programming, there is no time axis, no concept of "earlier" or
> "later".

Interesting point. I hadn't thought about this.

Is the whole point of functional programming to allow better 
optimization by the processor / compiler? Or are there other advantages 
as well?

> The answer is to initialize the global variable to the subset of the
> document that's needed, from within its own initializer.

As I mentioned to John, I can't do this because the document name can 
change. If I could pass the document name from a point external to the 
library, this would solve my problem. (I suppose I should check the 
Saxon documentation and see if this is possible...)

> Incidentally, the problem of passing parameters through functions that don't
> actually look at them directly sounds like a request for something like XSLT
> 2.0's tunnel parameters.

It does.

> It looks as if XQuery is going to be extended to turn it into a procedural
> language through "scripting extensions". As far as I'm concerned, that's a
> great shame - being forced to learn to use functional programming has made
> me a much better programmer.

How so?

I've had to jump through a slightly different set of hoops, but it all 
feels about the same as performing structured programming. By 
"structured programming", I mean breaking your application into many 
small functions and only passing to each function the information it 
needs. This as opposed to 70s-style spaghetti code, with lots of global 
variables and GOTOs. That was a big difference for me and led to much 
cleaner code.

Of course, here I am asking for global variables :)

-- Ron



Purchase Stylus Studio Online Today!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Buy Stylus Studio Now

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Don't miss another message! Subscribe to this list today.
Email
First Name
Last Name
Company
Subscribe in XML format
RSS 2.0
Atom 0.3
Site Map | Privacy Policy | Terms of Use | Trademarks
Free Stylus Studio XML Training:
W3C Member
Stylus Studio® and DataDirect XQuery™are products from DataDirect Technologies, is a registered trademark of Progress Software Corporation, in the U.S. and other countries. © 2004-2007 All Rights Reserved.