Extracts a single character from a string using a (1-based) index.
Extracts the named entry from the STRUCT.
Extracts the entry from an unnamed STRUCT (tuple) using an index (1-based).
Extracts a single character from a string using a (1-based) index.
Extracts the named entry from the STRUCT.
Extracts the entry from an unnamed STRUCT (tuple) using an index (1-based).