Adds alias_name to a named alias collection under set_name. Skips empty
values, an alias already registered for that set, and set names that are
themselves alias values (which would chain l to l1).
Usage
register_index_alias(collection, set_name, alias_name)
Arguments
- collection
Named character vector of aliases (set name -> alias).
- set_name
Name of the set to alias.
- alias_name
Alias to register.
Value
The collection with the alias appended, or unchanged.
