DEELX supports Perl compatible regular expression syntax. The basic patterns in DEELX are the same as it in most engines.
Alphas, numbers, the underscore and punctuations with no special definition are "common chars".
Simple escaped characters
Some nonprinting characters which we know.
Quoted characters (\Q...\E)
Quote (disable) pattern metacharacters from \Q till \E.
Can match any one but only one character of a certain set of characters.
Custom defined character sets
Use square [ ] to define a custom character set.
Make another expression repeat matching many times.
A condition of the position, does not match any character.
Use "|" to separate expressions, match any one and only one of them.
Use bracket ( ) to enclose sub-expressions into a single element.
Name a group, then get what captured through the name.
Refer to what a certain group captured.