In this course, you'll study the fundamentals and principles of functional programming.

ocaml_utop_haskell.tar.gz

OCaml

Functional programming is a paradigm that builds complete applications by breaking down programs into constituent functions that empowers developers to build fast, bug-resistant applications.

You’ll be introduced to functional programming with illustrative examples contrasting the more widely used imperative programming paradigm. You’ll review lambda calculus as an introduction to expressions, the building blocks of functional programs. You’ll continue with abstractions and complex data types before exploring common computation patterns. Next, you’ll learn how dataflows create whole programs out of existing functions. Finally, you’ll finish by applying your functional programming knowledge to various real-world scenarios. At each step, you’ll learn OCaml and Haskell, while contrasting imperative programming with Java.

By the end of this course, you’ll be prepared to use functional programming in your daily work and have the framework to know when to use either imperative or functional paradigms.

Mastering Functional Programming with OCaml and Haskell

## Limitations of list-based dataflow programming

The functional paradigm allows us to formulate programs in the dataflow style by composing function lists, such as `map`, `filter`, and `fold`. Unfortunately, list-based dataflow programming in OCaml has a severe limitation—lists are finite.


To illustrate, suppose we implement a function called `first_prime_greater_equal`. This function returns the first prime number greater than or equal to a given `n`. We can attempt to formulate a dataflow program to solve this problem with the following steps:

* Enumerate integers greater than or equal `n` 
* Filter the list, keeping only prime numbers
* Take the head of the resulting list

In other words, we attempt to formulate the following dataflow diagram:


# Limitations of list-based dataflow programming

The functional paradigm allows us to formulate programs in the dataflow style by composing function lists, such as `map`, `filter`, and `fold`. Unfortunately, list-based dataflow programming in OCaml has a severe limitation—lists are finite.


To illustrate, suppose we implement a function called `first_prime_greater_equal`. This function returns the first prime number greater than or equal to a given `n`. We can attempt to formulate a dataflow program to solve this problem with the following steps:

* Enumerate integers greater than or equal `n` 
* Filter the list, keeping only prime numbers
* Take the head of the resulting list

In other words, we attempt to formulate the following dataflow diagram:


Understand how streams allow us to formulate dataflow programs that work with signals of infinite elements.

Introduction

Expressions: Building Blocks of Functional Programs

Building Abstractions with Functions

Compound Data Types

Common Computation Patterns

Dataflow Programming with Functions

Applying Functional Programming to Various Domains

Conclusion

Appendix

Stream-based Dataflow Programming

Limitations of list-based dataflow programming