Compaq's Web Language

Frequently Asked Questions

General

Installation

Answers

Why the name change?

The name was changed in order to avoid a possible trademark conflict.

Why the parrot?

We are often asked why Compaq's Web Language has a parrot as a mascot. The simple answer is that we don't really know why. It's like asking why does Java have a pointy pillow with a round nose as a mascot.

How can I keep up to date on developments with Compaq's Web Language? Is there a mailing list?

More information on joining the mailing list and keeping up to date on developments can be found here.

Is Compaq's Web Language 100% pure Java?

On UNIX, yes. On Windows, no. The Compaq's Web Language Browser module needs a Windows DLL to display output inside your web browser. If you don't need this functionality, scripts are portable (in so far as you have not introduced your own specific machine dependencies by using platform specific shell commands or file name conventions).

Is Compaq's Web Language a compiler or interpreter?

An interpreter. This means things tend to run much slower than you would want. There are no plans to build a compiler.

Do you have scripts for extracting information from Web site X?

Maybe. Check the examples page for details. Otherwise I am afraid you have to code up a script yourself.

What about bad HTML/XML? How robust is your HTML/XML parser?

Compaq's Web Language tries to make a faithful representation of whatever Web page it parses. This involves fixing as few things as possible (mainly inserting optional end-tags and removing element overlaps). For HTML this involves looking at the Document Type Definition (DTD). The page parsers are hand-coded for speed.

Compaq's Web Language has no function to do X. What are my options?

Many functions are still missing from the alpha version. Mail us if you are looking for something particular (which does not guarantee you will have it in the next release). You also have the option of coding your own functions in Compaq's Web Language itself, or directly in Java. In case you want to restrict yourself to using Compaq's Web Language only, the Java bridge functions of module Java can help you access functionality of the underlying Java platform via the Java reflection API.

I would like to process pages in non-western encodings. Can Compaq's Web Language do this?

Yes, except we have not had much experience with this feature yet. Mail us if you find any problems.

Can I execute UNIX/DOS shell commands from Compaq's Web Language?

Yes. The Exec and Call functions allow the execution of shell commands.

How do you access an object field like "Content-Type" that is not a valid identifier?

Writing obj.x is equivalent to writing obj["x"] in your programs. You can thus access the object field with obj["Content-Type"].

On which versions of the JDK does Compaq's Web Language run?

Only JDK versions 1.1 or later. Compaq's Web Language requires the Java character converter classes of JDK 1.1 to parse pages written in Unicode or non-Latin alphabets.

On which platforms did you test Compaq's Web Language?

Only Windows NT and Digital UNIX.

I am behind a firewall. How do I tell Compaq's Web Language about the proxy server?

Compaq's Web Language uses the default proxies set up by your Java virtual machine (as defined by Sun's HotJava browser). Unfortunately most stand-alone Java installations are NOT set up correctly. To solve this problem, Compaq's Web Language attempts to read a properties file called "webl.properties" from the working directory, which contains additional configuration parameters (including the proxy settings). The contents of this file typically looks something like the following:

#
# webl properties
#

http.proxySet=true
http.proxyHost=www-proxy.pa.dec.com
http.proxyPort=8080
http.nonProxyHosts=*.pa.dec.com

ftpProxySet=true
ftpProxyHost=www-proxy.pa.dec.com
ftpProxyPort=8080
ftpNonProxyHosts=*.pa.dec.com

UNIX: Is it possible to run Compaq's Web Language scripts by making them executable?

Yes. The normal #! convention is supported (Compaq's Web Language will skip over the first line of a script that contains this incantation).

Compaq's Web Language runs too slow. What can I do about it?

There might be a few reasons for this. Check your memory usage (Compaq's Web Language keeps everything in memory, including complete copies of pages). Fetching pages from the web is often slower that you might think! And remember that interpreters are generally quite slow.