Mask email local part
This function masks all characters before the @ character. Two methods are available: By character and From a list of values.
This function only applies on Strings.
This function requires an extra parameter.
| Option | Description | 
|---|---|
| Method | When using the By
						character method, this function masks what comes before the @
					character with a character. When using the From a list of values method, this function masks what comes before the @ character with one of the values from the specified list.  | 
         
| Extra parameter | 
               This function requires an extra parameter.
                When using the By character method, the extra parameter must be a character. If you specify an invalid extra parameter, like a string, a list, multiple characters or a digit, all characters before the @ character will be masked with X characters by default. When using the From a list of values, the extra parameter can be a comma-separated list of values or a path to a file containing a list of values. If you do not specify an extra parameter, all characters before the @ character are removed.  | 
         
In the second example, all characters before the @ character are masked with one of the values from the user-defined list.
| Input value | Method | Extra parameter | Example of masked value | 
|---|---|---|---|
| johnsmith@company.com | By character | "p" | ppppppppp@company.com | 
| johnsmith@company.com | From a list of values | "z,x,c,h" | xxxxxxxxx@company.com |