A dynamic family

This family builds families dynamically. >>> [!note] Informations **dyn*a***
**dyn*b***
`standard` **Identifiers**:
- a
- b >>> | Variable | Description | |-------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------| | **dyn*a*.var**
**dyn*b*.var**
[`string`](https://rougail.readthedocs.io/en/latest/variable.html#variables-types) `standard` `mandatory` | A variable inside dynamic family.
**Default**: val |