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instance method

String#downcase!

downcase!(*options) → self or nil

Downcases the characters in self; returns self if any changes were made, nil otherwise:

Example
s = 'Hello World!' # => "Hello World!"
s.downcase!        # => "hello world!"
s                  # => "hello world!"
s.downcase!        # => nil

The casing may be affected by the given options; see Case Mapping.

Related: String#downcase, String#upcase, String#upcase!.

See also #downcase #dump #delete_suffix! #each_byte also in 4.1 · 4.0 · 3.4 · 3.2 · 3.1 · 3.0