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instance method

String#upcase!

() -> self?
(:ascii | :lithuanian | :turkic) -> self?
(:lithuanian, :turkic) -> self?
(:turkic, :lithuanian) -> self?
upcase!(*options) → self or nil

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

Example
s = 'Hello World!' # => "Hello World!"
s.upcase!          # => "HELLO WORLD!"
s                  # => "HELLO WORLD!"
s.upcase!          # => nil

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

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

See also #upcase #upto #unpack1 #valid_encoding? also in 4.1 · 4.0 · 3.3 · 3.2 · 3.1 · 3.0