NMPDR Development Blog

If you use Firefox, you should consider installing the Web Developer Toolbar at http://chrispederick.com/work/webdeveloper/. It allows you to view the current web page's cookies, form data, and style information (among other things). Plus, there's a little icon on the far right that turns red if there's an error in the page. This last is particularly helpful for navigating through JavaScript and style problems.

The new tracing system has been updated so that it works on the bio* machines. To use the system, start at /FIG/Html/SetPassword.html on whichever version of SEED you're debugging. Contact me via EMAIL if you don't know the password. Fill your name or something similar into the Tracing Key field, then submit the form. This will take you to the Sprout debugging console. The tracing form is at the bottom.

Click here for information on how to enable your web scripts for tracing and generate trace messages. When you activate tracing using the Emergency Tracing form on the debug page, it creates a file in the FIG temporary directory. Your tracing key is stored in a cookie as long as you stay on the debug form, and the web scripts can use the cookie to find the temporary file and turn on the type of tracing indicated. There are also buttons on the form for turning off tracing and for showing the tracing file.

The Tracer.pm module contains several utilities for processing tab-delimited files. Although none of these methods do anything spectacular, they take some of the tedium out of this kind of programming.

• Open opens a file and dies with an error message if the open fails.
• GetLine reads a line from the file, chops off the new-line, and splits it into pieces on tab boundaries.
• PutLine takes a list of text elements, joins them together with tabs, appends a new-line, and writes the result. This is basically the opposite of GetLine.

A sample program using these methods is shown below the fold.

There is now an online Flash tutorial available that describes how to use the tracing system. Included are sections on how to enable tracing, how to configure it from the web console or the command line, and how to put tracing statements in your code.

The URL is http://www.figresearch.com/movies/Tracing.html. A link to it is listed on the sidebar of the NMPDR Development Blog. The tutorial works in Firefox on the Mac and the PC, and Internet Explorer on the PC. It does not yet work in Safari, due to a problem with Safari being unable to recognize the Flash Player version. (It's always something.)

The tutorial is divided into several small sections that can be viewed individually, so that it should not be a burden to read through it. The first time you load it, the introductory animation will play a portion of Ellie's Favorite Fugue, so turn the volume down if you don't want to hear it. After that, you will be taken directly to the menu.