Definition
/**
* This functions is an alias for creating string entry from null.
* The main difference between using this function an simply str_entry with second argument null
* is that this function will also keep a note in the metadata that type might not be final.
* For example when we need to guess column type from rows because schema was not provided,
* and given column in the first row is null, it might still change once we get to the second row.
* That metadata is used to determine if string_entry was created from null or not.
*
* By design flow assumes when guessing column type that null would be a string (the most flexible type).
*/
null_entry(string $name) : StringEntry
