LAPIS - Multiple Constraints

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Multiple Constraints

You can attach more than one constraint to a pattern by putting more constraints on later lines. For example:

Notice that the second line is indented so that ending lines up with starting. That indentation is necessary -- it tells the system that ending is modifying Word, just like starting does. Notice the light blue line connecting ending with Word. This line indicates how the system is interpreting your indentation. You don't have to draw the line yourself. Just indent, and lines will be drawn automatically.

Try entering this pattern now. To insert a line break without running the pattern, use Shift-Enter (hold down the Shift key while pressing Enter). Be careful to reproduce the indentation.

Jared L. Cohon
Carnegie Mellon University
5000 Forbes Ave
Pittsburgh PA 15213

Charles M. Vest
Massachusetts Institute of Technology
77 Massachusetts Ave
Cambridge MA 02139

Notice that the pattern selects all words that start with the letter c and end with the letter e. If you know logic, this is a Boolean and of the two constraints.
A constraint can also modify the object of another constraint. For example:

Enter this pattern now. You should see that it selects any sentence containing a state name, where the state name must start with T, as in Texas.

Note that it would be okay to put the second constraint, starting "T", on the next line, as long as it is indented far enough that it affects State instead of Sentence (as indicated by the light blue line).

But if you indent the second line less, so that starting is connected to Sentence instead of State, you'll get a different meaning.

Try this pattern now, and notice that it selects sentences that happen to contain any state (like New Jersey), but only if the sentence itself begins with T.

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