Searching and replacing

The dialog boxes of searching an replacng have such parameters:

A string to find.
Replace by (in the replace dialog box only)
String, which will substitute the found pattern.
Case sensitive
Consider case of letters (if it is off, capital and small letters are equal).
Whole word
Search only those entries, which are whole words, but not part of a word (for example, if the patter is "or", then only conjunctions "or" will be found, but not all suffixes "or").
Regular expressions
Use regular expressions for searching.

Regular expressions

In regular expressions, in addition to ordinary symbols, the following metasymbols can be used:

Beginning of line.
End of line.
Any symbol.
Interpret next symbol literally.
Zero or more times.
One or more times.
Exactly n times.
Not less than n times.
From n to m times.
[ ]
Any simbol from the set (a range is indicated by symbol -); for example, [aeiou0-9] matches any symbol of a, e, i, o, u, and digit from 0 to 9; other operators and metasymbols don't work in the brackets.
[^ ]
None of the set, for example, [aeiou0-9] is none of the set a, e, i, o, u, and none of digits from 0 to 9.
Any alpha-numeric symbol (including "_").
Any non-alphanumeric symbol.
Space symbol (space or tab).
Non-space symbol.
Tab symbol.
Line delimiter (for multi-lines patterns).
Previous or next pattern, for example, fee|fie|foe means "fee" or "fie" or "foe".
( )
The round brackets group a subexpression, which can be used for replace.

Metasymbols for replace of regular expressions

$0 or $&
Whole found regular expression.
$n (n>0)
Subexpression in round brackets number n (from left to right beginning from one). If you need place a digit just after $n, place n in braces: ${12}4.