the main ARN name (everything after the underscore if undername exists, or the full name if top-level)
Extracts the undername portion from the full ARNS name.
the undername if present, undefined if this is a top-level ARN
Checks if this ARNS name contains an undername.
true if the name contains an underscore, indicating an undername is present
Extracts the main ARN name from the full ARNS name.