Registers a new date format for formatting Time instances. See Time::DATE_FORMATS for built-in formats. Use the format name as the name and either a strftime string or Proc instance that takes a date argument as the value.
Time
Time::DATE_FORMATS
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# File activesupport/lib/active_support/time_formats.rb, line 38 def self.register(name, format) @list = @list.merge(name => format).freeze end