Occam (programming Language)
   HOME
*



picture info

Occam (programming Language)
occam is a programming language which is concurrent and builds on the communicating sequential processes (CSP) process algebra, Inmos document 72 occ 45 03 and shares many of its features. It is named after philosopher William of Ockham after whom Occam's razor is named. occam is an imperative procedural language (such as Pascal). It was developed by David May and others at Inmos (trademark INMOS), advised by Tony Hoare, as the native programming language for their transputer microprocessors, but implementations for other platforms are available. The most widely known version is occam 2; its programming manual was written by Steven Ericsson-Zenith and others at Inmos. Overview In the following examples indentation and formatting are critical for parsing the code: expressions are terminated by the end of the line, lists of expressions need to be on the same level of indentation. This feature, named the off-side rule, is also found in other languages such as Haskell and Pytho ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Imperative Programming
In computer science, imperative programming is a programming paradigm of software that uses statements that change a program's state. In much the same way that the imperative mood in natural languages expresses commands, an imperative program consists of commands for the computer to perform. Imperative programming focuses on describing ''how'' a program operates step by step, rather than on high-level descriptions of its expected results. The term is often used in contrast to declarative programming, which focuses on ''what'' the program should accomplish without specifying all the details of ''how'' the program should achieve the result. Imperative and procedural programming Procedural programming is a type of imperative programming in which the program is built from one or more procedures (also termed subroutines or functions). The terms are often used as synonyms, but the use of procedures has a dramatic effect on how imperative programs appear and how they are constructed ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circuitry required to perform the functions of a computer's central processing unit. The integrated circuit is capable of interpreting and executing program instructions and performing arithmetic operations. The microprocessor is a multipurpose, clock-driven, register-based, digital integrated circuit that accepts binary data as input, processes it according to instructions stored in its memory, and provides results (also in binary form) as output. Microprocessors contain both combinational logic and sequential digital logic, and operate on numbers and symbols represented in the binary number system. The integration of a whole CPU onto a single or a few integrated circuits using Very-Large-Scale Integration (VLSI) greatly reduced the cost of ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Recursion (computer Science)
In computer science, recursion is a method of solving a computational problem where the solution depends on solutions to smaller instances of the same problem. Recursion solves such recursive problems by using functions that call themselves from within their own code. The approach can be applied to many types of problems, and recursion is one of the central ideas of computer science. Most computer programming languages support recursion by allowing a function to call itself from within its own code. Some functional programming languages (for instance, Clojure) do not define any looping constructs but rely solely on recursion to repeatedly call code. It is proved in computability theory that these recursive-only languages are Turing complete; this means that they are as powerful (they can be used to solve the same problems) as imperative languages based on control structures such as and . Repeatedly calling a function from within itself may cause the call stack to have a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Protocol (object-oriented Programming)
In object-oriented programming, an interface or protocol type is a data type describing a set of method signatures, the implementations of which may be provided by multiple classes that are otherwise not necessarily related to each other. A class which provides the methods listed in a protocol is said to ''adopt'' the protocol, or to ''implement'' the interface. If objects are fully encapsulated then the protocol is the only way in which they may be accessed by other objects. For example, in Java, the Comparable interface specifies a method compareTo() which implementing classes must implement. This means that a sorting method, for example, can sort a collection of any objects of types which implement the Comparable interface, without having to know anything about the inner nature of the class (except that two of these objects can be compared by means of compareTo()). Some programming languages provide explicit language support for protocols (Ada, C#, D, Dart, Delphi, Go, Ja ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Nesting (computing)
In computing science and informatics, nestinghttps://study.com/academy/lesson/nesting-loops-statements-in-c-programming.html, title=Nesting Loops & Statements in C Programming is where information is organized in layers, or where objects contain other similar objects. It almost always refers to self-similar or recursive structures in some sense. Terminology Nesting can mean: * nested calls: ** using several levels of subroutines ** recursive calls * nested levels of parentheses in arithmetic expressions * nested blocks of imperative source code such as nested if-clauses, while-clauses, repeat-until clauses etc. * information hiding: ** nested function definitions with lexical scope ** nested data structures such as records, objects, classes, etc. * nested virtualization, also called recursive virtualization: running a virtual machine inside another virtual machine In spreadsheets In a spreadsheet functions can be ''nested'' one into another, making complex formulas. The func ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


π-calculus
In theoretical computer science, the -calculus (or pi-calculus) is a process calculus. The -calculus allows channel names to be communicated along the channels themselves, and in this way it is able to describe concurrent computations whose network configuration may change during the computation. The -calculus has few terms and is a small, yet expressive language (see ). Functional programs can be encoded into the -calculus, and the encoding emphasises the dialogue nature of computation, drawing connections with game semantics. Extensions of the -calculus, such as the spi calculus and applied , have been successful in reasoning about cryptographic protocols. Beside the original use in describing concurrent systems, the -calculus has also been used to reason about business processesOMG Specification (2011)"Business Process Model and Notation (BPMN) Version 2.0" ''Object Management Group''. p.21 and molecular biology. Informal definition The -calculus belongs to the family of proc ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Pi (letter)
Pi (uppercase Π, lowercase π and ϖ; el, πι ) is the sixteenth letter of the Greek alphabet, representing the voiceless bilabial plosive . In the system of Greek numerals it has a value of 80. It was derived from the Phoenician letter Pe (). Letters that arose from pi include Latin P, Cyrillic Pe (П, п), Coptic pi (Ⲡ, ⲡ), and Gothic pairthra (𐍀). Uppercase Pi The uppercase letter Π is used as a symbol for: * In textual criticism, '' Codex Petropolitanus'', a 9th-century uncial codex of the Gospels, now located in St. Petersburg, Russia. * In legal shorthand, it represents a plaintiff. In science and engineering: * The product operator in mathematics, indicated with capital pi notation (in analogy to the use of the capital Sigma as summation symbol). * The osmotic pressure in chemistry. * The viscous stress tensor in continuum mechanics and fluid dynamics. Lowercase Pi The lowercase letter π is used as a symbol for: * The mathematical real transcen ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


KRoC
Kroc is a surname. Notable people with the name include: * Janae Kroc (born 1972), bodybuilder and powerlifter * Joan Kroc (1929–2003), American philanthropist * Ray Kroc Raymond Albert Kroc (October 5, 1902 – January 14, 1984) was an American businessman. He purchased the fast food company McDonald's in 1961 and was its CEO from 1967 to 1973. Kroc is credited with the global expansion of McDonald's, turnin ... (1902–1984), American founder of McDonald's See also * People with the surname ''Krock'' * People with the surname ''Krok'' {{surname ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Floating-point
In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can be represented as a base-ten floating-point number: 12.345 = \underbrace_\text \times \underbrace_\text\!\!\!\!\!\!^ In practice, most floating-point systems use base two, though base ten (decimal floating point) is also common. The term ''floating point'' refers to the fact that the number's radix point can "float" anywhere to the left, right, or between the significant digits of the number. This position is indicated by the exponent, so floating point can be considered a form of scientific notation. A floating-point system can be used to represent, with a fixed number of digits, numbers of very different orders of magnitude — such as the number of meters between galaxies or between protons in an atom. For this reason, floating-poi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

1983 Programming Manual Occam By INMOS Limited
The year 1983 saw both the official beginning of the Internet and the first mobile cellular telephone call. Events January * January 1 – The migration of the ARPANET to TCP/IP is officially completed (this is considered to be the beginning of the true Internet). * January 24 – Twenty-five members of the Red Brigades are sentenced to life imprisonment for the 1978 murder of Italian politician Aldo Moro. * January 25 ** High-ranking Nazi war criminal Klaus Barbie is arrested in Bolivia. ** IRAS is launched from Vandenberg AFB, to conduct the world's first all-sky infrared survey from space. February * February 2 – Giovanni Vigliotto goes on trial on charges of polygamy involving 105 women. * February 3 – Prime Minister of Australia Malcolm Fraser is granted a double dissolution of both houses of parliament, for elections on March 5, 1983. As Fraser is being granted the dissolution, Bill Hayden resigns as leader of the Australian Labor Party, and in the subseq ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Guard (computer Science)
In computer programming, a guard is a boolean expression that must evaluate to true if the program execution is to continue in the branch in question. Regardless of which programming language is used, a guard clause, guard code, or guard statement, is a check of integrity preconditions used to avoid errors during execution. Uses A typical example is checking that a reference about to be processed is not null, which avoids null-pointer failures. Other uses include using a boolean field for idempotence (so subsequent calls are nops), as in the dispose pattern. public string Foo(string username) Flatter code with less nesting The guard provides an early exit from a subroutine, and is a commonly used deviation from structured programming, removing one level of nesting and resulting in flatter code: replacing if guard with if not guard: return; .... Using guard clauses can be a refactoring technique to improve code. In general, less nesting is good, as it simplifies the code an ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Blocking (computing)
In computing, a process is an instance of a computer program that is being executed. A process always exists in exactly one process state. A process that is blocked is one that is waiting for some event, such as a resource becoming available or the completion of an I/O operation. In a multitasking computer system, individual tasks, or threads of execution, must share the resources of the system. Shared resources include: the CPU, network and network interfaces, memory and disk. When one task is using a resource, it is generally not possible, or desirable, for another task to access it. The techniques of mutual exclusion are used to prevent this concurrent use. When the other task is blocked, it is unable to execute until the first task has finished using the shared resource. Programming languages and scheduling algorithms are designed to minimize the over-all effect blocking. A process that blocks may prevent local work-tasks from progressing. In this case "blocking" often i ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]