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rubysyntaxcoffeescript

Differences between the ruby 2.3 safe operator "&." and CoffeeScript existential operator ".?"

What, if any, are the differences between the ruby 2.3 safe operator &. and the CoffeeScript existential operator .?

Solution

  • CoffeeScript's existential operator ? returns true unless a variable is null or undefined, which makes it analogous to Ruby's nil?

    Instead, the new Ruby safe navigation operator &. is used to call a method of an Object that can be nil without raising an exception. If the object is not nil, the method will be executed; otherwise, it returns nil.

    Something like this:

    obj.try!(:method1).try!(:method2)

if obj && obj.method1
  #...
end

    becomes:

    obj&.method1&.method2

if obj&.method1
  #...
end

    References: