3.1 Reducers

      3.1.1 Reducer Constructors

      3.1.2 Reducer Operators

      3.1.3 Iteration and Comprehension with Reducers

      3.1.4 Reducer Contracts

      3.1.5 Reducer Chaperones and Impersonators

      3.1.6 Legacy Reduction APIs

    3.2 Transducers

      3.2.1 Transforming Elements with Transducers

      3.2.2 Removing Elements with Transducers

      3.2.3 Adding Elements with Transducers

      3.2.4 Rearranging Elements with Transducers

      3.2.5 Transducer Composition

      3.2.6 The Transduction Protocol

      3.2.7 Transducer Contracts

      3.2.8 Transducer Chaperones and Impersonators

      3.2.9 Debugging Transducers

      3.2.10 Testing Transducers