Comparison Of Type Systems
This is a comparison of the features of the type systems and type checking of multiple programming languages. Brief definitions * A nominal type system means that the language decides whether types are compatible and/or equivalent based on explicit declarations and names. * A structural type system A structural type system (or property-based type system) is a major class of type systems in which type compatibility and equivalence are determined by the type's actual structure or definition and not by other characteristics such as its name ... means that the language decides whether types are compatible and/or equivalent based on the definition and characteristics of the types. * ''Type checking'' determines whether and when types are verified. Static checking means that type errors are reported based on a program's text (source code). Dynamic checking means that type errors are reported based on a program's dynamic (run-time) behavior. Notes References {{reflist * *< ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Type System
In computer programming, a type system is a logical system comprising a set of rules that assigns a property called a ''type'' (for example, integer, floating point, string) to every '' term'' (a word, phrase, or other set of symbols). Usually the terms are various language 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 data types, such as "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 synta ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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ALGOL 58
ALGOL 58, originally named IAL, is a member of the ALGOL family of computer programming languages. It was an early compromise design soon superseded by ALGOL 60. According to John Backus: The Zurich ACM-GAMM Conference had two principal motives in proposing the IAL: (a) To provide a means of communicating numerical methods and other procedures between people, and (b) To provide a means of realizing a stated process on a variety of machines... ALGOL 58 introduced the fundamental notion of the compound statement, but it was restricted to control flow only, and it was not tied to identifier scope in the way that Algol 60's blocks were. Name Bauer attributes the name to Hermann Bottenbruch, who coined the term ''algorithmic language'' (algorithmische Sprache) in 1957, "at least in Germany". History There were proposals for a universal language by the Association for Computing Machinery (ACM) and also by the German Gesellschaft für Angewandte Mathematik und Mechanik ("Society of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Assembly Language
In computing, assembly language (alternatively assembler language or symbolic machine code), often referred to simply as assembly and commonly abbreviated as ASM or asm, is any low-level programming language with a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Assembly language usually has one statement per machine instruction (1:1), but constants, comments, assembler directives, symbolic labels of, e.g., memory locations, registers, and macros are generally also supported. The first assembly code in which a language is used to represent machine code instructions is found in Kathleen and Andrew Donald Booth's 1947 work, ''Coding for A.R.C.''. Assembly code is converted into executable machine code by a utility program referred to as an '' assembler''. The term "assembler" is generally attributed to Wilkes, Wheeler and Gill in their 1951 book '' The Preparation of Programs for an Electronic Dig ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Arc (programming Language)
Arc is a programming language, a dialect of the language Lisp, developed by Paul Graham and Robert Morris. It is free and open-source software released under the Artistic License 2.0. History In 2001, Paul Graham announced that he was working on a new dialect of Lisp named ''Arc''. Over the years since, he has written several essays describing features or goals of the language, and some internal projects at Graham's startup business incubator named Y Combinator have been written in Arc, most notably the Hacker News web forum and news aggregator program. Arc is written in Racket. Motives In the essay ''Being Popular'' Graham describes a few of his goals for the language. While many of the goals are very general ("Arc should be hackable", "there should be good libraries"), he did give some specifics. For example, he believes it is important for a language to be terse: He also stated that it is better for a language to only implement a small number of ''axioms'', even whe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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AppleScript
AppleScript is a scripting language created by Apple Inc. that facilitates automated control of Mac applications. First introduced in System 7, it is currently included in macOS in a package of automation tools. The term ''AppleScript'' may refer to the scripting language, to a script written in the language, or to the macOS Open Scripting Architecture that underlies the language. AppleScript is primarily a mechanism for driving Apple events an inter-application communication (IAC) technology that exchanges data between and controls applications. Additionally, AppleScript supports basic calculations and text processing, and is extensible via scripting additions that add functions to the language. AppleScript is tightly bound to the Mac environment, similar to how Windows Script Host is bound to the Windows environment. In other words, AppleScript is not a general purpose scripting language like Python. One way that AppleScript is bound to the unique aspects of its env ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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APL (programming Language)
APL (named after the book ''A Programming Language'') is a programming language developed in the 1960s by Kenneth E. Iverson. Its central datatype is the multidimensional array. It uses a large range of special graphic symbols to represent most functions and operators, leading to very concise code. It has been an important influence on the development of concept modeling, spreadsheets, functional programming, and computer math packages. It has also inspired several other programming languages. History Mathematical notation A mathematical notation for manipulating arrays was developed by Kenneth E. Iverson, starting in 1957 at Harvard University. In 1960, he began work for IBM where he developed this notation with Adin Falkoff and published it in his book ''A Programming Language'' in 1962. The preface states its premise: This notation was used inside IBM for short research reports on computer systems, such as the Burroughs B5000 and its stack mechanism when stack m ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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AngelScript
AngelScript is an open-source game-oriented compiled scripting language developed by Andreas Jönsson at AngelCode. AngelScript features static typing, object handles (similar to C++ pointers but garbage collected via reference counting), object-orientation, single inheritance, multiple inheritance with interfaces. It allows operators to be registered and overloaded. AngelScript can be used with any C++ IDE, such as NetBeans, Geany, and Eclipse. C and C++ functions can be called within an AngelScript environment. AngelScript's class syntax closely follows C++ classes by design: no proxy functions are required to embed AngelScript in C++ applications, easing the two languages' integration. There are several differences of AngelScript and C++: * AngelScript does not support multiple inheritance. Multiple-inheritance functionality may be achieved with Interfaces. * It is impossible to declare methods or properties outside of the class body. * All methods (including constructo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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AMOS (programming Language)
AMOS BASIC is a dialect of the BASIC programming language for the Amiga computer. Following on from the successful STOS BASIC for the Atari ST, AMOS BASIC was written for the Amiga by François Lionet with Constantin Sotiropoulos and published by Europress Software in 1990. The language was notable for its focus on media and game development capabilities, allowing users to easily create demanding multimedia software and games. It featured full structured code and numerous high-level functions for loading and manipulating images, animations, and sounds. These capabilities made it a popular choice among Amiga enthusiasts, particularly beginners, for creating video games (especially platformers and graphical adventures), multimedia applications, and educational software. History AMOS competed on the Amiga platform with Acid Software's Blitz BASIC. Both BASICs differed from other dialects on different platforms, in that they allowed the easy creation of fairly demanding multimedi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Alma-0
Alma-0 is a multi-paradigm computer programming language. This language is an augmented version of the imperative Modula-2 language with logic-programming features and convenient backtracking ability. It is small, strongly typed, and combines constraint programming, a limited number of features inspired by logic programming and supports imperative paradigms. The language advocates declarative programming. The designers claim that search-oriented solutions built with it are substantially simpler than their counterparts written in purely imperative or logic programming style. Alma-0 provides natural, high-level constructs for building search trees. Overview Since the designers of Alma-0 wanted to create a distinct and substantially simpler proposal than prior attempts to integrate declarative programming constructs (such as automatic backtracking) into imperative programming, the design of Alma-0 was guided by four principles: * The logic-based extension should be ''downward'' com ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Alice (programming Language)
Alice ML is a general-purpose, high-level, multi-paradigm, functional programming language designed by the Programming Systems Laboratory at Saarland University, Saarbrücken, Germany. It is a dialect of Standard ML, augmented with support for lazy evaluation, concurrency ( multithreading and distributed computing via remote procedure calls) and constraint programming. Overview Alice extends Standard ML in a number of ways that distinguish it from its predecessor. Alice provides concurrency features as part of the base language through the use of a ''future'' type that represents a value being provided by an independent thread of execution. A thread that uses a future value will block on an attempt to access the value until the thread performing it has completed the computation. A related concept is also provided termed a '' promise'', allowing a thread to provide a future value that it will compute to another thread. Future and promise typed variables are used to implemen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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ALGOL W
ALGOL W is a programming language. It is based on a proposal for ALGOL X by Niklaus Wirth and Tony Hoare as a successor to ALGOL 60. ALGOL W is a relatively simple upgrade of the original ALGOL 60, adding string, bitstring, complex number and reference to record data types and call-by-result passing of parameters, introducing the while statement, replacing switch with the case statement, and generally tightening up the language. Wirth's entry was considered too little of an advance over ALGOL 60, and the more complex entry from Adriaan van Wijngaarden that would later become ALGOL 68 was selected in a highly contentious meeting. Wirth later published his version as ''A contribution to the development of ALGOL''. With a number of small additions, this eventually became ALGOL W. Wirth supervised a high quality implementation for the IBM System/360 at Stanford University that was widely distributed. (Various documents for Stanford's 1972 implementation of ALGOL W; this ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |