Commands

Keep/Omit

In the Pattern box at right, type row contains M in 4th cell in row and press Enter to select the courses that meet on Monday. Then pull down the Tools menu and select Keep. The course list should now show only the classes that were selected. The same result could be achieved by selecting the courses that don't meet on Monday (row not containing M in 4th cell in row) and invoking Tools/Omit instead.

Sort

In the Pattern box at right, type row and press Enter. Then pull down the Tools menu and select Sort. A dialog box should appear. In the "Part of record matching" box, type 3rd cell in row, and press OK. The course list should now be sorted by lecturer's name.

15-712	Advanced Operating Systems	Gibson	MW	10:00-11:20	WeH 5409A&B	12
15-750	Algorithms	Blum/Sleator	TR	1:30-2:50	WeH 5409A&B	9
15-780/16-731	Advanced AI Concepts	Moore	TR	10:30-11:50	WeH 5409A&B	12
20-602/15-802	Statistical Approaches to Learning	Fienberg/Lafferty	TR	12:00-1:20	PH A22	12
15-819	Typed Compilation	Crary	MW	1:30-2:50	WeH 5409B	12
15-819	Denotational Semantics of  Types	Reynolds	TR	10:30-11:50	WeH 4601	9
15-812	Semantics of  Programming Languages	Brookes	MWF	10:00-10:50	WeH 4615A	12
15-810	Verification of Real-Time Programs	Clarke	M	12:30-1:50	WeH 4601	6
80-713	Category Theory	Awodey	TR	1:30-2:50		12
15-822	System Design and Implementation	Satya	T	3:00-5:50	WeH 8220	15
15-824	Mobile and Wireless Networking	Johnson	TR	10:30-11:50	WeH 4615A	12

extract word

Type or copy this command to the Command box, and press Enter. This command extracts all the words in this page. (Press the Back button to return to this page.) If you look at the Tools menu, you'll notice Extract is found there too. Each tool has a corresponding Tcl command: extract, keep, delete, sort, replace, calc, etc.

enter textbox rhizome ; click {first button}

The enter command puts "rhizome" in the textbox in the form below, just as if you had typed it. Then the click command clicks on the "Look up definition" button, which looks up "rhizome" in an online dictionary and returns a page showing its definition. (Press the Back button to return to this page.) This example shows how commands can be used to script web interactions.

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Hypertext Webster Gateway (http://smac.ucsd.edu/cgi-bin/http_webster)

Enter word here:
Exact Approx

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extract word -as text
sort word -order unicode
uniq

This example extracts the words from the page (as text, instead of the default HTML), sorts them (case-sensitively, instead of the default case-insensitive sort), and then runs the external program uniq to eliminate duplicates. (Note: Since Microsoft Windows doesn't have the uniq command, this command will probably fail on Windows.

ls
keep {line ending .html}
eval wc [lines]

This example runs ls to list the files in the current directory, filters to filenames ending ".html", and then runs the external program wc to count words in those files. (Note: Since Microsoft Windows doesn't have these external programs, this command will fail on Windows.) The last command needs some extra explanation: lines is a shortcut for extract Line -as tcl, which converts the lines in ls output into a Tcl list. The eval command then expands that list into arguments for wc. Without eval,wc would see only one argument containing all the filenames, instead of one argument for each filename. 

More Information

• Command Reference