Ωmega
   HOME





Ωmega
The Omega interpreter is a strict pure functional programming interpreter similar to the Hugs Haskell interpreter. The syntax closely resembles that of Haskell but with important differences: * Omega uses strict evaluation (Hugs uses lazy evaluation); * Ability to introduce new kinds; * Allows writing functions at the type level. Other differences are documented in the Omega user guide. Omega was developed by Professor Tim Sheard of Portland State University Portland State University (PSU) is a public research university in Portland, Oregon, United States. It was founded in 1946 as a post-secondary educational institution for World War II veterans. It evolved into a four-year college over the next ...'s Computer Science Department as a language with an infinite hierarchy of computational levels, e.g., value, type, kind, sort. The underlying concept is that data, and functions manipulating data, can be introduced at any level. References External links * , with download ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Haskell
Haskell () is a general-purpose, statically typed, purely functional programming language with type inference and lazy evaluation. Designed for teaching, research, and industrial applications, Haskell pioneered several programming language features such as type classes, which enable type-safe operator overloading, and monadic input/output (IO). It is named after logician Haskell Curry. Haskell's main implementation is the Glasgow Haskell Compiler (GHC). Haskell's semantics are historically based on those of the Miranda programming language, which served to focus the efforts of the initial Haskell working group. The last formal specification of the language was made in July 2010, while the development of GHC continues to expand Haskell via language extensions. Haskell is used in academia and industry. , Haskell was the 28th most popular programming language by Google searches for tutorials, and made up less than 1% of active users on the GitHub source code repository ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Portland State University
Portland State University (PSU) is a public research university in Portland, Oregon, United States. It was founded in 1946 as a post-secondary educational institution for World War II veterans. It evolved into a four-year college over the next 20 years and was granted university status in 1969. It is one of two public universities in Oregon that are in a large city. It is governed by a board of trustees. PSU is classified among "R2: Doctoral Universities – High research activity". Portland State comprises seven constituent colleges, offering undergraduate degrees in 123 fields and postgraduate degrees in 117 fields. As of 2023, the university had a total enrollment of approximately 21,000 students. Its athletic teams are known as the Portland State Vikings, with school colors of green and white. They compete at the NCAA Division I level, primarily in the Big Sky Conference. History 1946–1964: Establishment Portland State University was established as the Vanport Exte ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cross-platform Software
Within computing, cross-platform software (also called multi-platform software, platform-agnostic software, or platform-independent software) is computer software that is designed to work in several computing platforms. Some cross-platform software requires a separate build for each platform, but some can be directly run on any platform without special preparation, being written in an interpreted language or compiled to portable bytecode for which the interpreters or run-time packages are common or standard components of all supported platforms. For example, a cross-platform application may run on Linux, macOS and Microsoft Windows. Cross-platform software may run on many platforms, or as few as two. Some frameworks for cross-platform development are Codename One, ArkUI-X, Kivy, Qt, GTK, Flutter, NativeScript, Xamarin, Apache Cordova, Ionic, and React Native. Platforms ''Platform'' can refer to the type of processor (CPU) or other hardware on which an operating syste ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Interpreter (computing)
In computer science, an interpreter is a computer program that directly executes instructions written in a programming or scripting language, without requiring them previously to have been compiled into a machine language program. An interpreter generally uses one of the following strategies for program execution: # Parse the source code and perform its behavior directly; # Translate source code into some efficient intermediate representation or object code and immediately execute that; # Explicitly execute stored precompiled bytecode made by a compiler and matched with the interpreter's virtual machine. Early versions of Lisp programming language and minicomputer and microcomputer BASIC dialects would be examples of the first type. Perl, Raku, Python, MATLAB, and Ruby are examples of the second, while UCSD Pascal is an example of the third type. Source programs are compiled ahead of time and stored as machine independent code, which is then linked at run-ti ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


BSD Licenses
BSD licenses are a family of permissive free software licenses, imposing minimal restrictions on the use and distribution of covered software. This is in contrast to copyleft licenses, which have share-alike requirements. The original BSD license was used for its namesake, the Berkeley Software Distribution (BSD), a Unix-like operating system. The original version has since been revised, and its descendants are referred to as modified BSD licenses. BSD is both a license and a class of license (generally referred to as BSD-like). The modified BSD license (in wide use today) is very similar to the license originally used for the BSD version of Unix. The BSD license is a simple license that merely requires that all code retain the BSD license notice if redistributed in source code format, or reproduce the notice if redistributed in binary format. The BSD license (unlike some other licenses e.g. GPL) does not require that source code be distributed at all. Terms In addition to ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Strict Function
In computer science and computer programming, a function f is said to be strict if, when applied to a non-terminating expression, it also fails to terminate. A strict function in the denotational semantics of programming languages is a function ''f'' where f\left(\perp\right) = \perp. The entity \perp, called '' bottom'', denotes an expression that does not return a normal value, either because it loops endlessly or because it aborts due to an error such as division by zero. A function that is not strict is called non-strict. A strict programming language is one in which user-defined functions are always strict. Intuitively, non-strict functions correspond to control structures. Operationally, a strict function is one that always evaluates its argument; a non-strict function is one that might not evaluate some of its arguments. Functions having more than one parameter can be strict or non-strict in each parameter independently, as well as ''jointly strict'' in several parameter ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Pure Function
In computer programming, a pure function is a function that has the following properties: # the function return values are identical for identical arguments (no variation with local static variables, non-local variables, mutable reference arguments or input streams, i.e., referential transparency), and # the function has no side effects (no mutation of non-local variables, mutable reference arguments or input/output streams). Examples Pure functions The following examples of C++ functions are pure: Impure functions The following C++ functions are impure as they lack the above property 1: The following C++ functions are impure as they lack the above property 2: The following C++ functions are impure as they lack both the above properties 1 and 2: I/O in pure functions I/O is inherently impure: input operations undermine referential transparency, and output operations create side effects. Nevertheless, there is a sense in which a function can perform inpu ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Functional Programming
In computer science, functional programming is a programming paradigm where programs are constructed by Function application, applying and Function composition (computer science), composing Function (computer science), functions. It is a declarative programming paradigm in which function definitions are Tree (data structure), trees of Expression (computer science), expressions that map Value (computer science), values to other values, rather than a sequence of Imperative programming, imperative Statement (computer science), statements which update the State (computer science), running state of the program. In functional programming, functions are treated as first-class citizens, meaning that they can be bound to names (including local Identifier (computer languages), identifiers), passed as Parameter (computer programming), arguments, and Return value, returned from other functions, just as any other data type can. This allows programs to be written in a Declarative programming, d ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Hugs (interpreter)
Hugs (Haskell User's Gofer System), also Hugs 98, is a bytecode interpreter for the functional programming language Haskell. Hugs is the successor to Gofer, and was originally derived from Gofer version 2.30b. Hugs and Gofer were originally developed by Mark P. Jones, now a professor at Portland State University. Hugs comes with a simple graphics library. As a complete Haskell implementation that is portable and simple to install, Hugs is sometimes recommended for new Haskell users. Hugs deviates from the Haskell 98 specification in several minor ways. For example, Hugs does not support mutually recursive modules. A list of differences exists. The Hugs prompt is a Haskell read–eval–print loop A read–eval–print loop (REPL), also termed an interactive toplevel or language shell, is a simple interactive computer programming environment that takes single user inputs, executes them, and returns the result to the user; a program written ... (REPL). It accepts expressions ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Evaluation Strategy
In a programming language, an evaluation strategy is a set of rules for evaluating expressions. The term is often used to refer to the more specific notion of a ''parameter-passing strategy'' that defines the kind of value that is passed to the function for each parameter (the ''binding strategy'') and whether to evaluate the parameters of a function call, and if so in what order (the ''evaluation order''). The notion of reduction strategy is distinct, although some authors conflate the two terms and the definition of each term is not widely agreed upon. A programming language's evaluation strategy is part of its high-level semantics. Some languages, such as PureScript, have variants with different evaluation strategies. Some declarative languages, such as Datalog, support multiple evaluation strategies. The calling convention consists of the low-level platform-specific details of parameter passing. Example To illustrate, executing a function call f(a,b) may first evaluat ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lazy Evaluation
In programming language theory, lazy evaluation, or call-by-need, is an evaluation strategy which delays the evaluation of an Expression (computer science), expression until its value is needed (non-strict evaluation) and which avoids repeated evaluations (by the use of Sharing (computer science), sharing). The benefits of lazy evaluation include: * The ability to define control flow (structures) as abstractions instead of Language primitive, primitives. * The ability to define actual infinity, potentially infinite data structures. This allows for more straightforward implementation of some algorithms. * The ability to define partly-defined data structures where some elements are errors. This allows for rapid prototyping. Lazy evaluation is often combined with memoization, as described in Jon Bentley (computer scientist), Jon Bentley's ''Writing Efficient Programs''. After a function's value is computed for that Parameter (computer programming), parameter or set of parameters, th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]