[RUBY] Easy to use array.map (&: method)

Easy to use array.map (&: method)

Example

Suppose you have the following formula. Convert each element to uppercase in the block and store it in an array.

['a', 'b', 'c'].map{|s| s.upcase } #=> ["A", "B", "C"]

Easy to use array.map (&: method)

You can easily follow the above example using array.map (&: method).

['a', 'b', 'c'].map(&:upcase) # => ["A", "B", "C"]

Applicable condition

  1. Only one block argument
  2. The method you call inside the block has no arguments
  3. Inside the block, there is no processing other than calling the method for the block argument

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