module

Enumerable(T)

The Enumerable mixin provides collection classes with several traversal, searching, filtering and querying methods.

Including types must provide an each method, which yields successive members of the collection.

For example:

class Three
  include Enumerable(Int32)

  def each(&)
    yield 1
    yield 2
    yield 3
  end
end

three = Three.new
three.to_a                # => [1, 2, 3]
three.select &.odd?       # => [1, 3]
three.all? { |x| x < 10 } # => true

Note that most search and filter methods traverse an Enumerable eagerly, producing an Array as the result. For a lazy alternative refer to the Iterator and Iterable modules.

Instance methods

find_value(fallback = nil, &)

Yields each value until the first truthy block result and returns that result.

Accepts an optional parameter if_none, to set what gets returned if no element is found (defaults to nil).

[1, 2, 3, 4].find_value { |i| i > 2 }     # => true
[1, 2, 3, 4].find_value { |i| i > 8 }     # => nil
[1, 2, 3, 4].find_value(-1) { |i| i > 8 } # => -1

Source