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Multitier Programming
Multitier programming (or tierless programming) is a programming paradigm for distributed software, which typically follows a multitier architecture, physically separating different functional aspects of the software into different ''tiers'' (e.g., the client, the server and the database in a Web application). Multitier programming allows functionalities that span multiple of such tiers to be developed in a single compilation unit using a single programming language. Without multitier programming, tiers are developed using different languages, e.g., JavaScript for the Web client, PHP for the Web server and SQL for the database. Multitier programming is often integrated into general-purpose languages by extending them with support for distribution. Concepts from multitier programming were pioneered by the Hop and Links languages and have found industrial adoption in solutions such as Ocsigen, Opa,Rajchenbach-Teller, D., & Sinot, Franois-Régis. (2010). Opa: Language support for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programming Paradigm
Programming paradigms are a way to classify programming languages based on their features. Languages can be classified into multiple paradigms. Some paradigms are concerned mainly with implications for the execution model of the language, such as allowing side effects, or whether the sequence of operations is defined by the execution model. Other paradigms are concerned mainly with the way that code is organized, such as grouping a code into units along with the state that is modified by the code. Yet others are concerned mainly with the style of syntax and grammar. Common programming paradigms include: * imperative in which the programmer instructs the machine how to change its state, ** procedural which groups instructions into procedures, ** object-oriented which groups instructions with the part of the state they operate on, * declarative in which the programmer merely declares properties of the desired result, but not how to compute it ** functional in which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macroprogramming
In computer science, macroprogramming is a programming paradigm aimed at expressing the macroscopic, global behaviour of an entire system of agents or computing devices. In macroprogramming, the local programs for the individual components of a distributed system are compiled or interpreted from a ''macro-program'' typically expressed by a system-level perspective or in terms of the intended global goal. The aim of macroprogramming approaches is to support expressing the macroscopic interactive behaviour of a whole distributed system of computing devices or agents in a single program, or, similarly, to promote their collective intelligence. It has not to be confused with macros, the mechanism often found in programming languages (like C or Scala) to express substitution rules for program pieces. Macroprogramming originated in the context of wireless sensor network programming and found renewed interest in the context of the Internet of Things and swarm robotics. Macroprogramm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defunctionalization
In programming languages, defunctionalization is a compile-time transformation which eliminates higher-order functions, replacing them by a single first-order ''apply'' function. The technique was first described by John C. Reynolds in his 1972 paper, "Definitional Interpreters for Higher-Order Programming Languages". Reynolds' observation was that a given program contains only finitely many function abstractions, so that each can be assigned and replaced by a unique identifier. Every function application within the program is then replaced by a call to the ''apply'' function with the function identifier as the first argument. The ''apply'' function's only job is to dispatch on this first argument, and then perform the instructions denoted by the function identifier on the remaining arguments. One complication to this basic idea is that function abstractions may reference free variables. In such situations, defunctionalization must be preceded by closure conversion (lambda li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continuation Passing Style
In functional programming, continuation-passing style (CPS) is a style of programming in which control is passed explicitly in the form of a continuation. This is contrasted with direct style, which is the usual style of programming. Gerald Jay Sussman and Guy L. Steele, Jr. coined the phrase in AI Memo 349 (1975), which sets out the first version of the Scheme programming language. John C. Reynolds gives a detailed account of the numerous discoveries of continuations. A function written in continuation-passing style takes an extra argument: an explicit "continuation"; ''i.e.'', a function of one argument. When the CPS function has computed its result value, it "returns" it by calling the continuation function with this value as the argument. That means that when invoking a CPS function, the calling function is required to supply a procedure to be invoked with the subroutine's "return" value. Expressing code in this form makes a number of things explicit which are implicit in dire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type System
In computer programming, a type system is a logical system comprising a set of rules that assigns a property called a type to every "term" (a word, phrase, or other set of symbols). Usually the terms are various constructs of a computer program, such as variables, expressions, functions, or modules. A type system dictates the operations that can be performed on a term. For variables, the type system determines the allowed values of that term. Type systems formalize and enforce the otherwise implicit categories the programmer uses for algebraic data types, data structures, or other components (e.g. "string", "array of float", "function returning boolean"). Type systems are often specified as part of programming languages and built into interpreters and compilers, although the type system of a language can be extended by optional tools that perform added checks using the language's original type syntax and grammar. The main purpose of a type system in a programming langu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annotation
An annotation is extra information associated with a particular point in a document or other piece of information. It can be a note that includes a comment or explanation. Annotations are sometimes presented in the margin of book pages. For annotations of different digital media, see web annotation and text annotation. Literature and education Textual scholarship Textual scholarship is a discipline that often uses the technique of annotation to describe or add additional historical context to texts and physical documents to make it easier to understand. Student uses Students often highlight passages in books in order to refer back to key phrases easily, or add marginalia to aid studying. Annotated bibliographies add commentary on the relevance or quality of each source, in addition to the usual bibliographic information that merely identifies the source. Mathematical expression annotation Mathematical expressions (symbols and formulae) can be annotated with their natura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-stage Programming
Multi-stage programming (MSP) is a variety of metaprogramming in which compilation is divided into a series of intermediate phases, allowing typesafe run-time code generation. Statically defined types are used to verify that dynamically constructed types are valid and do not violate the type system. In MSP languages, expressions are qualified by notation that specifies the phase at which they are to be evaluated. By allowing the specialization of a program at run-time, MSP can optimize the performance of programs: it can be considered as a form of partial evaluation that performs computations at compile-time as a trade-off to increase the speed of run-time processing. Multi-stage programming languages support constructs similar to the Lisp construct of quotation and eval, except that scoping In computer programming, the scope of a name binding (an association of a name to an entity, such as a variable) is the part of a program where the name binding is valid; that is, where the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compiler
In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that translate source code from a high-level programming language to a low-level programming language (e.g. assembly language, object code, or machine code) to create an executable program. Compilers: Principles, Techniques, and Tools by Alfred V. Aho, Ravi Sethi, Jeffrey D. Ullman - Second Edition, 2007 There are many different types of compilers which produce output in different useful forms. A '' cross-compiler'' produces code for a different CPU or operating system than the one on which the cross-compiler itself runs. A '' bootstrap compiler'' is often a temporary compiler, used for compiling a more permanent or better optimised compiler for a language. Related software include, a program that translates from a low-level language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multitier Architecture
In software engineering, multitier architecture (often referred to as ''n''-tier architecture) is a client–server architecture in which presentation, application processing and data management functions are physically separated. The most widespread use of multitier architecture is the three-tier architecture. ''N''-tier application architecture provides a model by which developers can create flexible and reusable applications. By segregating an application into tiers, developers acquire the option of modifying or adding a specific tier, instead of reworking the entire application. A three-tier architecture is typically composed of a ''presentation'' tier, a ''logic'' tier, and a ''data'' tier. While the concepts of layer and tier are often used interchangeably, one fairly common point of view is that there is indeed a difference. This view holds that a ''layer'' is a logical structuring mechanism for the conceptual elements that make up the software solution, while a ''tier'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Network
A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are made up of telecommunication network technologies, based on physically wired, optical, and wireless radio-frequency methods that may be arranged in a variety of network topologies. The nodes of a computer network can include personal computers, servers, networking hardware, or other specialised or general-purpose hosts. They are identified by network addresses, and may have hostnames. Hostnames serve as memorable labels for the nodes, rarely changed after initial assignment. Network addresses serve for locating and identifying the nodes by communication protocols such as the Internet Protocol. Computer networks may be classified by many criteria, including the transmission medium used to carry signals, bandwidth, communications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregate Computing
Aggregate or aggregates may refer to: Computing and mathematics * collection of objects that are bound together by a root entity, otherwise known as an aggregate root. The aggregate root guarantees the consistency of changes being made within the aggregate by forbidding external objects from holding references to its members. * Aggregate (data warehouse), a part of the dimensional model that is used to speed up query time by summarizing tables * Aggregate analysis, a technique used in amortized analysis in computer science, especially in analysis of algorithms * Aggregate class, a type of class supported by C++ * Aggregate data, in statistics, data combined from several measurements * Aggregate function, aggregation function, in database management is a function wherein the values of multiple rows are grouped together to form a single summary value * Aggregate Level Simulation Protocol (ALSP), a protocol and supporting software that enables simulations to interoperate with one ano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choreographic Programming
In computer science, choreographic programming is a programming paradigm where programs are compositions of interactions among multiple concurrent participants. Overview Choreographies In choreographic programming, developers use a choreographic programming language to define the intended communication behaviour of concurrent participants. Programs in this paradigm are called choreographies. Choreographic languages are inspired by security protocol notation (also known as "Alice and Bob" notation). The key to these languages is the communication primitive, for example Alice.expr -> Bob.x reads "Alice communicates the result of evaluating the expression expr to Bob, which stores it in its local variable x". Alice, Bob, etc. are typically called roles or processes. The example below shows a choreography for a simplified single sign-on (SSO) protocol based on a Central Authentication Service (CAS) that involves three roles: * Client, which wishes to obtain an access token fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
