Concatenative programming language

From Wikipedia, the free encyclopedia

Programming paradigms

Agent-oriented Component-based Flow-based Pipeline Concatenative Concurrent computing Declarative (contrast: Imperative) Functional Dataflow Cell-oriented (spreadsheets) Reactive Goal-directed Constraint Constraint logic Logic Abductive logic Inductive logic Event-driven Feature-oriented Function-level (contrast: Value-level) Imperative (contrast: Declarative) Greater separation of concerns Aspect-oriented Subject-oriented Array (contrast: Scalar) Automata-based Object-oriented Class-based Prototype-based Procedural Structured Role-oriented Scalar (contrast: Array) Iterative (contrast: Recursive) Metaprogramming Attribute-oriented Automatic Generic Template Policy-based Language-oriented Grammar-oriented Dialecting Intentional Reflective Modular Nondeterministic Parallel computing Process-oriented Programming in the large and programming in the small Recursive (contrast: Iterative) Tree Value-level (contrast: Function-level) This box: view • talk • edit

A concatenative programming language is one in which all terms denote functions and the juxtaposition of terms denotes function composition. ^{[1] [2]} The combination of a compositional semantics with a syntax that mirrors such a semantics makes concatenative languages highly amenable to algebraic manipulation and formal analysis.^[3]

Much of the original work on concatenative language theory was carried out by Manfred von Thun. Today, the majority of discussion regarding concatenative languages takes place on the concatenative mailing list.

Contents 1 Properties 2 Implementations 3 See also 4 External links 5 References

[edit] Properties

The properties of concatenative languages are the result of their compositional syntax and semantics:

• Concatenative languages are necessarily point-free as allowing terms to denote variables would violate the rule that all terms denote functions.
• The reduction of any expression is the simplification of one function to another function; it is never necessary to deal with the application of functions to objects.^[4]
• Any subexpression can be replaced with a name that represents the same subexpression. This is referred to in the concatenative community as factoring and is used extensively to simplify programs into smaller parts.
• The syntax and semantics of concatenative languages form the algebraic structure of a monoid.^[5]
• Concatenative languages are well-suited to a "linear logic" implementation, meaning that no garbage is ever generated.^[6]

[edit] Implementations

The first concatenative programming language was Forth, although Joy was the first language to call itself concatenative. Other concatenative languages are Cat, Enchilada, Factor, Onyx, PostScript, RPL, Stappl, and XY.

Most existing concatenative languages are stack-based; this is not a requirement and other models have been proposed.^[2] Concatenative languages are currently used for embedded, desktop, and web programming, as target languages, and for research purposes. Most concatenative languages are untyped, although Cat is typed and proposals for other typed languages have been made.^[7]

[edit] See also

• Function-level programming
• Point-free programming
• Stack-based programming languages

[edit] External links

• Manfred von Thun's Joy and concatenative theory website
• The concatenative mailing list
• concatenative.org: A wiki about concatenative languages

[edit] References