Summary

In this chapter, we introduced lambda calculus as the basis for the functional programming paradigm. In functional programming, programs are written in a declarative language, expressing the desired result as a composition of functions instead of a procedural set of steps to execute.

In Java and Python, this appears as lambda expressions or lambda functions - small pieces of code that can be used to create anonymous functions. In addition, those functions can be treated as first-class citizens in our language, so we can store them in variables, pass them as arguments, and more.

However, due to the fact that lambda expressions are not well understood by a large number of programmers who do not have experience with functional programming, we’ll generally avoid their use in our code. In most cases, anything that can be done in a lambda expression can also be done using procedural code and functions, and that is much more readable to the average programmer.

Review Quiz

Check your understanding of the new content introduced in this chapter below - this quiz is not graded and you can retake it as many times as you want.