7 Components: the Function Pages - Developers

Boolean
operations
Tab. 13.1
Examples
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complex topic that would fill bookshelves. However, we nevertheless
want to try to give you an idea of what they are.
In a RegEx search, there is also the option of using Boolean operations:
Expression Result
Term1;Term2 AND operation. Both terms must be present.
This operator is specific to TWiki.
Term1|Term2 OR operation. At least one of the terms must be
found.
!Term1 NOT operation. The term entered must not appear
in the document.
(expression) Collection of several expressions to make a single
unit having processing priority.
There are a few more points to remember. First of all, make sure you
do not insert any spaces. They are not ignored in RegEx, but rather
processed along with the rest. That means if there is a space before a
term, the character string “term” will be searched. Secondly, as the
above table shows, words can be collected into a single unit using
parentheses; these will be processed first. The order of the expression
priority is PARENTHESES before NOT before AND before
OR. Thirdly, employing brackets also enables unlimited nesting of
expressions. This option facilitates very complex searches.
A few examples will illustrate the functions described. For instance,
the word
torch|torches
is not only searched in the singular, but also in the plural. We can
combine them to search for torchlights as well:
torch(light|lights)
Note that the entire term will be searched as one unit. Thus, pages
containing just “torch” or just “light” will be ignored. A search for a
torchlight from a flaming torch, excluding light from a flashlight,
which in British English is called an (electric) torch, might look like
this:
torch(light|lights);!electric
13 Searching in TWiki