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Regular Expressions

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					                                                                                    MUSO: Blackboard
Regular Expressions                                                                                  MU46

Definition:

A regular expression, or regex for short, can be used to indentify strings of text or patterns of characters.
They are written in a formal language, and depending on the pattern matching you are trying to achieve
can be quite complicated. Blackboard accepts the Perl standard of regular expressions.


Using regular expressions in Blackboard:

Data validation of responses to short answer questions can be achieved through the use of regular
expressions, which can match a student’s answer to predetermined patterns in order to grade
responses. Great care needs to be taken as it’s difficult to predict all possible permutations and
combinations that students may enter while still being correct (depending on the discipline of course). A
detailed discussion of possible regexes is well outside the scope of this document, but the following
resources are a good places to start:

       http://www.regular-expressions.info/, general information
       http://members.ziggo.nl/h.schotel/testaregex/, useful for testing your regexes
       http://oreilly.com/catalog/9780596528126/, the definitive reference guide
       http://search.cpan.org/~nwclark/perl-5.8.3/pod/perlretut.pod
       http://www.weitz.de/regex-coach/




Regular Expressions (mu46)                                                                                 1
v1.0 prepared by Anthony Richardson

				
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Description: Regular Expressions