Clojure Overview

I love Clojure because its powerful, flexible and fun.

Here are a selection of features which appealed to me when I first looked at Clojure

Dynamic Language & runtime environment (REPL)

• quickly explore your problem domain by coding in the REPL
• very minimal boilerplate code (reduced even more with macros)
• new code is compiled as evaluated, no seperate compile cycle or wait time
• very small language syntax, extensible via macros

'Pure' Functional Programming

• encourages an immutable approach that helps keep the code simple
• minimising state changes makes scaling your application easy
• Persistent data structures (List, Map, Vector, Set) give an efficient way of modifying data without side effects

Managed State Changes

• Reference types atoms & refs for mutable state
• Changes are done safely within Software Transactional Memory (STM), like having an in-memory ACID database managing all state changes under the covers.

Hosted on the JVM & consise interoperabilty

• Clojure is compiled to bytecode, giving very high performance (close to Java, C++, etc.)
• Simple syntax to call any other code that runs on the JVM (Java, Scala, JRuby, Jython, etc)

A modular / component approach to design

A typical approach with Clojure is to break a big problem space into many small libraries, each with a specific perpose. This helps deconstruct complex systems into smaller, easier to understand code. This also helps make these Clojure libraries reusable in many other projects, reducing the development effort.