Wilma can use regular expressions to match content words, file names and folder paths. In each case the regular expression is applied to each word, name or path individually. In other words you can not use something like:

Fred.*Tom

to match the multiple words in the phrase "Fred and Tom" although Wilma's proximity operators can be used for that purpose, but not when using regular expressions.

Regular expressions can be used with the logical operators when searching for content words, but the operators must be separated from the regular expressions by spaces. Spaces are not allowed in Wilma regular expressions.

A full description of regular expressions is beyond the scope of this documentation, but there is a vast amount of information on this subject on the net. The regular expression engine used in Wilma is derived from the PCRE package developed by Philip Hazel of the University of Cambridge. Below is a brief description of the syntax of regular expressions, largely taken from the REALbasic documentation.

Pattern Description
. Matches any character except newline.
[a-z0-9] Matches any single character of set.
[^a-z0-9] Matches any single character not in set.
\d Matches a digit. Same as [0-9].
\D Matches a non-digit. Same as [^0-9].
\w Matches an alphanumeric (word) character -- [a-zA-Z0-9_].
\W Matches a non-word character [^a-zA-Z0-9_].
\s Matches a whitespace character (space, tab, newline, etc.).
\S Matches a non-whitespace character.
\n Matches a newline (line feed).
\r Matches a return.
\t Matches a tab.
\f Matches a formfeed.
\b Matches a backspace.
\0 Matches a null character.
\000 Also matches a null character because of the following:
\nnn Matches an ASCII character of that octal value.
\xnn Matches an ASCII character of that hexadecimal value.
\cX Matches an ASCII control character.
\metachar Matches the meta-character (e.g., \, ., |).
(abc) Used to create subexpressions. Remembers the match for later back references. Referenced by replacement patterns that use \1, \2, etc.
\1, \2, Matches whatever first (second, and so on) of parens matched.
x? Matches 0 or 1 x's, where x is any of above.
x* Matches 0 or more x's.
x+ Matches 1 or more x's.
x{m,n} Matches at least m x's, but no more than n.
abc Matches all of a, b, and c in order.
a|b|c Matches one of a, b, or c.
\b Matches a word boundary (outside [] only).
\B Matches a non-word boundary.
^ Anchors match to the beginning of a line or string. In Wilma's case, this would be the beginning of the word, name, or folder path.
$ Anchors match to the end of a line or string. In Wilma's case, this would be the end of the word, name, or folder path.