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Shen Professional


August 2016

Shen Professional 10 moves into the cloud and acquires graphics.

June 2016

Shen Professional includes provision for large scale file handling.

May 2016

Shen Professional includes a computably effective axiomatic semantics P for generating formal descriptions of Shen programs in second-order logic.

April 2016

Shen Professional supports SML 1.0.  Shen Markup Language generates HTML from type secure Shen.

March 2016

Shen Professional supports full concurrency - communicating parallel processes with local state.

February 2016

Shen Professional supports non-communicating parallel processes.

September 2015

Shen Professional is launched - the project to build a commercial closed-source version of Shen.

February 2015

The Shen kernel goes BSD.



Shen is a portable functional programming language that offers
  • pattern matching,
  • lambda calculus consistency,
  • macros,
  • optional lazy evaluation,
  • static type checking,
  • one of the most powerful systems for typing in functional programming,
  • portability over many languages,
  • an integrated fully functional Prolog,
  • and an inbuilt compiler-compiler.

The word ‘Shen’ is Chinese for 'spirit' and our motto reflects our desire to liberate our work to live under many platforms. The Shen kernel is under BSD and currently runs under CLisp, SBCL, Clojure, Scheme, Ruby, Python, the JVM, Haskell and Javascript. To begin to learn Shen, browse the Learn Shen section.

We host an interactive Javascript page of the Shen REPL from this site - to use it click here.

Shen Professional is a closed source high performance development of the Shen kernel incorporating features for commercial deliverables.

Want to learn Shen from the ground up?

Shen has emerged as one of the most portable and far-reaching integrations of two great programming paradigms - functional and logic programming. The third edition to The Book of Shen gives the foundations of both those disciplines, exploring both lambda calculus, type theory, first - order and Horn clause logic in a text which is rich in worked examples. In the course of 400 pages, the text gives a complete formal and informal exposition of Shen.

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Want to learn the logical background to Shen?

Beginning with a review of formal languages and their syntax and semantics, Logic, Proof and Computation conducts a computer assisted course in formal reasoning and the relevance of logic to mathematical proof, information processing and philosophy. Topics covered include formal grammars, semantics of formal languages, sequent systems, truth-tables, propositional and first order logic, identity, proof heuristics, regimentation, set theory, databases, automated deduction, proof by induction, Turing machines, undecidability and a computer illustration of the reasoning underpinning Godel's incompleteness proof. LPC is designed as a multidisciplinary reader for students in computing, philosophy and mathematics.

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