yield_self_then

🛠️ Chaining with yield_self and then

Use yield_self (aliased as then) to inject intermediate operations into a fluent pipeline without breaking the chain. Particularly useful when you need side‑effects or conditional transformations.

result = [1,2,3]
  .map(&:to_s)
  .then { |arr| puts "Strings: #{arr.join(',')}"; arr }
  .filter { |s| s.start_with?('2') }

p result # => ["2"]