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Active Oberon
Active Oberon is a general purpose programming language developed during 1996–1998 by the group around Niklaus Wirth and Jürg Gutknecht at the Swiss Federal Institute of Technology in Zürich (ETH Zurich). It is an extension of the programming language Oberon (programming language), Oberon. The extensions aim at implementing active Object (computer science), objects as expressions for parallelism. Compared to its predecessors, Oberon and Oberon-2, Active Oberon adds objects (with object-centered access protection and local activity control), system-guarded assertions, preemptive priority scheduling and a changed Syntax (programming languages), syntax for Method (computer programming), methods (named ''Oberon-2#Type-bound procedures, type-bound procedures'' in Oberon vocabulary). Objects may be ''active'', which means that they may be Thread (computer science), threads or Process (computer science), processes. Unlike Java (programming language), Java or C Sharp (programming lang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperative Programming
In computer science, imperative programming is a programming paradigm of software that uses Statement (computer science), statements that change a program's state (computer science), state. In much the same way that the imperative mood in natural languages expresses commands, an imperative program consists of command (computing), commands for the computer to perform. Imperative programming focuses on describing ''how'' a program operates step by step (with general order of the steps being determined in source code by the placement of statements one below the other), 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. Procedural programming Procedural programming is a type of imperative programming in which the program is built from one or more procedures (also termed s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oberon-2
Oberon-2 is an extension of the original Oberon programming language that adds limited reflective programming (reflection) and object-oriented programming facilities, open arrays as pointer base types, read-only field export, and reintroduces the FOR loop from Modula-2. It was developed in 1991 at ETH Zurich by Niklaus Wirth and Hanspeter Mössenböck, who is now at Institut für Systemsoftware (SSW) of the University of Linz, Austria. Oberon-2 is a superset of Oberon, is fully compatible with it, and was a redesign of Object Oberon. Oberon-2 inherited limited reflection and single inheritance ("type extension") without the interfaces or mixins from Oberon, but added efficient virtual methods ("type bound procedures"). Method calls were resolved at runtime using C++-style virtual method tables. Compared to fully object-oriented languages like Smalltalk, in Oberon-2, basic data types and classes are not objects, many operations are not methods, there is no message pass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zonnon
Zonnon is a general purpose programming language in the line or family of the preceding languages Pascal, Modula, and Oberon. Jürg Gutknecht is the author. Its conceptual model is based on objects, definitions, implementations, and modules. Its computing model is concurrent, based on active objects which interact via syntax controlled dialogs. The language is being developed at ETH Zürich Institute for Computer Systems by Professor Jürg Gutknecht. Zonnon introduces the concept of 'active objects' which are used to represent real world concurrent objects within computer programs. The Zonnon Language Report was written by Brian Kirk (director at Robinsons Associates), and David Lightfoot (Oxford Brookes University) working with Gutknecht (ETH, Zürich) and Dr. Eugene Zueff (Евгений Зуев) (Moscow State University). The first book about Zonnon was published by the N. I. Lobachevsky State University of Nizhny Novgorod (a.k.a., Nizhni Novgorod State University). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fork (software Development)
In software development, a fork is a codebase that is created by duplicating an existing codebase and, generally, is subsequently modified independently of the original. Software built from a fork initially has identical behavior as software built from the original code, but as the source code is increasingly modified, the resulting software tends to have increasingly different behavior compared to the original. A fork is a form of branching, but generally involves storing the forked files separately from the original; not in the repository. Reasons for forking a codebase include user preference, stagnated or discontinued development of the original software or a schism in the developer community. Forking proprietary software (such as Unix) is prohibited by copyright law without explicit permission, but free and open-source software, by definition, may be forked without permission. Etymology The word ''fork'' has been used to mean "to divide in branches, go separate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A2 (operating System)
A2 (formerly named Active Object System (AOS), and then Bluebottle) is a modular, object-oriented operating system with features including automatic garbage-collected memory management, and a zooming user interface. It was developed originally at ETH Zurich in 2002. It is free and open-source software under a BSD-like license. History A2 is a successor to Native Oberon, the x86 PC version of Niklaus Wirth's operating system Oberon. Out of printElectronic reprint./ref> It supports multiprocessing computers, and provides soft real-time computing operation. It is entirely written in Active Oberon. User interface Bluebottle replaced the older Oberon OS's unique text-based user interface (TUI) with a zooming user interface (ZUI), which similar to a conventional graphical user interface (GUI). Like Oberon, though, its user interface supports a ''point and click'' interface metaphor to execute commands directly from text, similar to clicking hyperlinks in a web browser. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exception Handling (programming)
In computer programming, several language mechanisms exist for exception handling. The term ''exception'' is typically used to denote a data structure storing information about an exceptional condition. One mechanism to transfer control, or ''raise'' an exception, is known as a ''throw''; the exception is said to be ''thrown''. Execution is transferred to a ''catch''. Usage Programming languages differ substantially in their notion of what an exception is. Exceptions can be used to represent and handle abnormal, unpredictable, erroneous situations, but also as flow control structures to handle normal situations. For example, Python's iterators throw StopIteration exceptions to signal that there are no further items produced by the iterator. There is disagreement within many languages as to what constitutes idiomatic usage of exceptions. For example, Joshua Bloch states that Java's exceptions should only be used for exceptional situations, but Kiniry observes that Java's built ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal (computing)
Signals are standardized messages sent to a running program to trigger specific behavior, such as quitting or error handling. They are a limited form of inter-process communication (IPC), typically used in Unix, Unix-like, and other POSIX-compliant operating systems. A signal is an asynchronous notification sent to a process or to a specific thread within the same process to notify it of an event. Common uses of signals are to interrupt, suspend, terminate or kill a process. Signals originated in 1970s Bell Labs Unix and were later specified in the POSIX standard. When a signal is sent, the operating system interrupts the target process's normal flow of execution to deliver the signal. Execution can be interrupted during any non-atomic instruction. If the process has previously registered a signal handler, that routine is executed. Otherwise, the default signal handler is executed. Embedded programs may find signals useful for inter-process communications, as signals are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Sharp (programming Language)
C# ( pronounced: C-sharp) ( ) is a general-purpose high-level programming language supporting multiple paradigms. C# encompasses static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines. The principal inventors of the C# programming language were Anders Hejlsberg, Scott Wiltamuth, and Peter Golde from Microsoft. It was first widely distributed in July 2000 and was later approved as an international standard by Ecma (ECMA-334) in 2002 and ISO/ IEC (ISO/IEC 23270 and 20619) in 2003. Microsoft introduced C# along with .NET Framework and Microsoft Visual Studio, both of which are technically speaking, closed-source. At the time, Microsoft had no open-source products. Four years later, in 2004, a free and open-source project called Microsoft Mono began, providing a cross-platform compiler and runtime environment for the C# programming language. A decad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Java (programming Language)
Java is a High-level programming language, high-level, General-purpose programming language, general-purpose, Memory safety, memory-safe, object-oriented programming, object-oriented programming language. It is intended to let programmers ''write once, run anywhere'' (Write once, run anywhere, WORA), meaning that compiler, compiled Java code can run on all platforms that support Java without the need to recompile. Java applications are typically compiled to Java bytecode, bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. The syntax (programming languages), syntax of Java is similar to C (programming language), C and C++, but has fewer low-level programming language, low-level facilities than either of them. The Java runtime provides dynamic capabilities (such as Reflective programming, reflection and runtime code modification) that are typically not available in traditional compiled languages. Java gained popularity sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Process (computer Science)
In computing, a process is the Instance (computer science), instance of a computer program that is being executed by one or many thread (computing), threads. There are many different process models, some of which are light weight, but almost all processes (even entire virtual machines) are rooted in an operating system (OS) process which comprises the program code, assigned system resources, physical and logical access permissions, and data structures to initiate, control and coordinate execution activity. Depending on the OS, a process may be made up of multiple threads of execution that execute instructions Concurrency (computer science), concurrently. While a computer program is a passive collection of Instruction set, instructions typically stored in a file on disk, a process is the execution of those instructions after being loaded from the disk into memory. Several processes may be associated with the same program; for example, opening up several instances of the same progra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thread (computer Science)
In computer science, a thread of execution is the smallest sequence of programmed instructions that can be managed independently by a scheduler, which is typically a part of the operating system. In many cases, a thread is a component of a process. The multiple threads of a given process may be executed concurrently (via multithreading capabilities), sharing resources such as memory, while different processes do not share these resources. In particular, the threads of a process share its executable code and the values of its dynamically allocated variables and non- thread-local global variables at any given time. The implementation of threads and processes differs between operating systems. History Threads made an early appearance under the name of "tasks" in IBM's batch processing operating system, OS/360, in 1967. It provided users with three available configurations of the OS/360 control system, of which Multiprogramming with a Variable Number of Tasks (MVT) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Method (computer Programming)
A method in object-oriented programming (OOP) is a procedure associated with an object, and generally also a message. An object consists of ''state data'' and ''behavior''; these compose an ''interface'', which specifies how the object may be used. A method is a behavior of an object parametrized by a user. Data is represented as properties of the object, and behaviors are represented as methods. For example, a Window object could have methods such as open and close, while its state (whether it is open or closed at any given point in time) would be a property. In class-based programming, methods are defined within a class, and objects are instances of a given class. One of the most important capabilities that a method provides is '' method overriding'' - the same name (e.g., area) can be used for multiple different kinds of classes. This allows the sending objects to invoke behaviors and to delegate the implementation of those behaviors to the receiving object. A method in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
