class I18n::Config

def locale

Experimental RBS support (using type sampling data from the type_fusion project). 

def locale: () -> Symbol

This signature was generated using 22 samples from 4 applications.

It defaults to the default_locale.
The only configuration value that is not global and scoped to thread is :locale. 
def locale
  defined?(@locale) && @locale != nil ? @locale : default_locale
end