locale abstract method
Specifies the locale for which the collation will compare strings
appropriately based on the locale.
The locale must be specified as an
ISO-639 language
code plus, optionally, an underscore and an
ISO-3166
country code, e.g: "en", "en_US", "fr_CA", etc.
If not specified, the "en_US" locale will be used.
Implementation
UnicodeCollation locale(String? locale);