As a deeper example of interfacing with the MshHostRawUserInterface class, the next few articles will deal with implementing the classic “Fire Effect” seen in many of the demos that I so fondly remember.  As part of the journey, we’ll also explore some of the ways in which you can improve the performance of time-sensitive portions of your script.

[This GIF is animated.  Some Ad blocking software restricts animation]

What is the fire effect?  It’s a relatively simple algorithm to simulate fire – usually in a graphical buffer.  We’re going to do it in the console text buffer.  In the algorithm, you seed the bottom row randomly with hot pixels.  Then, you progress the fire upwards.  As you progress the fire upwards, you cool it off a little bit – and simulate heat dissipation by averaging the heat from nearby buffer cells.

For those of you looking to slake your thirst for Monad on something other than Blogs and Newsgroups, Andy Oakley’s book will soon be available from Amazon: http://www.amazon.com/gp/product/0596100094

It’s called “Monad – Introducing the MSH Command Shell and Language.”  I read it (several times) as one of the technical editors, and it’s a good piece of work.

[Edit: Monad has now been renamed to Windows PowerShell. This script or discussion may require slight adjustments before it applies directly to newer builds.]

As your scripts become more complex, it’s possible that you will have to interact with the user in a manner more complex than write- and read-host.  For example, you might decide to implement a text-based menu system, or even a game of Aliens.

To support this low-level access to the console buffer, hosts (for example, ours,) extend the MshHostRawUserInterface class.  This class provides most of the common operations required by a console-mode raw user interface, including window management, blitting, scrolling, and colour control.

Hopefully you’ve been following along with Eric’s regular expression exercises, because we’re about to add another cool tool to your Monad toolbox.  If your regex-fu is strong, you will soon dice text streams with ease.

As you well know, one of the strongest features of Monad is that the pipeline is object-based.  You don’t waste your energy creating, destroying, and recreating the object representation of your data.  In past shells, you destroy the full- fidelity representation of data when the pipeline converts it to pure text.  You can regain some of it through excessive text parsing, but not all of it. 

Somebody I work with recently tried to buy a camera from an internet retailer called “WaWaDigital.”  He was telling me about the low price they had it listed for, when the guy called him to confirm the order.

At this point, I recognized what was going on.  For some reason, there is an entire cottage industry (in the little cottage called Brooklyn, New York) that sells the camera for below cost, but cancels the order on you unless you buy hundreds of dollars of over-priced accessories.

One very significant problem in computer security is the “Dancing Pigs” syndrome [1][2]:

If J. Random Websurfer clicks on a button that promises dancing pigs on his computer monitor, and instead gets a hortatory message describing the potential dangers of the applet — he’s going to choose dancing pigs over computer security any day. If the computer prompts him with a warning screen like: “The applet DANCING PIGS could contain malicious code that might do permanent damage to your computer, steal your life’s savings, and impair your ability to have children,” he’ll click OK without even reading it. Thirty seconds later he won’t even remember that the warning screen even existed.

A fellow Microsoftie, “Jim of Seattle,” has been contributing pieces to songfight.org since 2003.  His most recent piece, “Welcome to ______,” adds another landslide win to his list.  (That’s 6 dashes, if you care.)  He takes the simple Windows XP startup theme, and then builds a nice classical melody around it.  Check it out – it’s truly cool.

He battles a powerful demon in this song – that being the strongly charged musical idiom.  In language, an idiom is “… an expression whose meaning is not compositional – that is, whose meaning does not follow from the meaning of the individual words of which it is composed” [Wikipedia]  A musical idiom is the musical equivalent – short advertising themes are probably the most common example.  He uses many of the default sounds from Windows – songs which are strongly tied to our computing instincts in many cases.  Without introducing the sounds carefully, it’s easy for a listener to get jarred from the mood of a piece because of an overwhelming urge to see what error dialog just popped up.

This is a “life hack” I’ve been meaning to share since I designed my very first GeoCities homepage, and I figure that now’s a good time to get off of my laurels and do it.  That is, memory and memorization techniques that I’ve found helpful through time.  Not that I’ve invented them, but that I use them.

[ Apple, Pencil, Fox, Anvil ]
- a list -

One difficult recall task we are often faced with is memorizing a list of things.  Remembering a shopping list.  Retaining a “to do” list.  However, the only reason it is difficult is that you haven’t (yet!) found a way to make it concrete, and less abstract.

As Adam points out in his most recent entry, our last release changed the default execution policy to a mode called “Restricted.”  The first time you run a script in the new shell, you’ll see the following error message:

The file C:\my_script.msh cannot be loaded. The execution of scripts
is disabled on this system. Please see “get-help about_signing” for
more details.

This is probably not the mode you want to stay with, as it doesn’t run those awesome scripts you write.  Yeah, that’s right, YOUR awesome scripts.  Remember how nice I’m being to you, as I’m about to ask a favour :)

Many thanks to Cyrus for pointing this out.  Videos from the PDC are now available for streaming via http://microsoft.sitestream.com/PDC05/.  The site is running rather slowly right now (it’s not being Slashdotted, that’s for sure,) so bring a bag of patience with you.

I, of course, recommend you start with Jeffrey and Jim’s Monad presentation (during which I was Proctoring at the hands-on-labs.)  As Jeffrey quotes, “This is not your Dad’s filesystem”.  Then, if you haven’t already, check out this year’s belle of the ball, Linq :)