For more than two years, Jens and Chema have worked hard to create what Phel is today. Phel is a Functional Programming language that compiles to PHP. It is a dialect of Lisp inspired by Clojure and Janet.

What does Phel look like? 

Here is an example of some Phel code from the website.

# Define a namespace
(ns my\example)

# Define a variable with name "my-name" and value "world"
(def my-name "world")

# Define a function with name "print-name" and one argument "your-name"
(defn print-name [your-name]
  (print "hello" your-name))

# Call the function
(print-name my-name)

Why Phel?

It is the result of many failed attempts to do functional programming in PHP.

We wanted to write a Lisp-inspired (Functional Programming) that runs on cheap hosting providers, and it’s easy to write and debug.

Object-Oriented vs Functional Programming

In OOP you manipulate objects (with methods), and they have a mutable state (as properties).

– Focus on “how you are doing”, mutable data, imperative programming, side effects, looping, …

In FP you have type structures that hold information, and everything else are functions.

– Focus on “how you are doing”, uses immutable data, declarative programming, no-side effects, recursion, …

How different is Phel from others?

Phel is highly inspired by Clojure, which runs on the JVM, and therefore it’s compatible with Java.

So, Phel is a dialect of Lisp that “compiles” to PHP, and therefore it’s 100% interoperable with PHP.

Features

– Built on PHP’s ecosystem

– Good error reporting

– Lists, Vectors, Maps and Sets

– Macros

– Recursive functions

– Powerful but simple Syntax

– REPL

Want to know more?

Visit the website at https://phel-lang.org and check out the GitHub repository.