# Array Regex Mask This is a [composite generator](https://docs.tonic.ai/app/generation/generators/generator-types/generators-composite). A version of the [Regex Mask](https://docs.tonic.ai/app/generation/generators/generator-reference/regex-mask) generator that can be used for array values. Uses regular expressions to parse strings and replace specified substrings with the output of specified generators. The parts of the string to replace are specified inside unnamed top-level capture groups. ## Characteristics


Consistency	Determined by the selected sub-generators.
Linking	Determined by the selected sub-generators.
Differential privacy	Determined by the selected sub-generators.
Data-free	Determined by the selected sub-generators.
Allowed for primary keys	No
Allowed for unique columns	No
Uses format-preserving encryption (FPE)	No
Privacy ranking	5
Generator ID (for the API)	`ArrayRegexMaskGenerator`

## How to configure ### Adding a regular expression To add a regular expression: 1. Click **Add Regex**.\ \ On the configuration panel, **Cell Value** shows a sample value from the source database. You can use the previous and next options to navigate through the values. 2. By default, **Replace all matches** is enabled.\ \ To only match the first occurrence of a pattern, toggle **Replace all matches** to the off position. 3. In the **Pattern** field, enter a regular expression.\ \ If the expression is valid, then Structural displays the capture groups for the expression. 4. For each capture group, to select and configure the generator to apply, click the selected generator.\ \ You cannot select another composite generator. 5. To save the configuration and immediately add a generator for another path expression, click **Save and Add Another**.\ \ To save the configuration and close the add generator panel, click **Save**. ### Managing the regular expressions list From the **Regexes** list: * To edit a regular expression, click the edit icon. * To remove a regular expression, click the delete icon.