The following syntactic features are supported:

• Logical Grouping : Group a part of the expression ((...)).
• Explicit Set : Define a set of possible characters ([...]). Ranges defined with a tiret are accepted.
• Explicit Quantifier : Specify the number of times the previous expression must be repeated. 'Constant' ({N}) or 'Range' ({N,M}) syntax are both accepted.
• Zero Or One Quantifier Metacharacter : 0 or 1 of the previous expression (?). Same effect as {0,1}.
• Escape Character : Makes the next character literal instead of a special character (\).