|
COMEFROM
In computer programming, COMEFROM (or COME FROM) is an obscure control flow structure used in some programming languages, originally as a joke. COMEFROM is the inverse of GOTO in that it can take the execution state from any arbitrary point in code to a COMEFROM statement. The point in code where the state transfer happens is usually given as a parameter to COMEFROM. Whether the transfer happens before or after the instruction at the specified transfer point depends on the language used. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, be executed in some sort of defined priority, or even induce parallel or otherwise concurrent execution as seen in Threaded Intercal. A simple example of a "COMEFROM x" statement is a label x (which does not need to be physically located anywhere near its corresponding COMEFROM) that acts as a "trap door". When code execution reaches the label, control gets passed to the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COMEFROM
In computer programming, COMEFROM (or COME FROM) is an obscure control flow structure used in some programming languages, originally as a joke. COMEFROM is the inverse of GOTO in that it can take the execution state from any arbitrary point in code to a COMEFROM statement. The point in code where the state transfer happens is usually given as a parameter to COMEFROM. Whether the transfer happens before or after the instruction at the specified transfer point depends on the language used. Depending on the language used, multiple COMEFROMs referencing the same departure point may be invalid, be non-deterministic, be executed in some sort of defined priority, or even induce parallel or otherwise concurrent execution as seen in Threaded Intercal. A simple example of a "COMEFROM x" statement is a label x (which does not need to be physically located anywhere near its corresponding COMEFROM) that acts as a "trap door". When code execution reaches the label, control gets passed to the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Flow
In computer science, control flow (or flow of control) is the order in which individual statements, instructions or function calls of an imperative program are executed or evaluated. The emphasis on explicit control flow distinguishes an ''imperative programming'' language from a '' declarative programming'' language. Within an imperative programming language, a ''control flow statement'' is a statement that results in a choice being made as to which of two or more paths to follow. For non-strict functional languages, functions and language constructs exist to achieve the same result, but they are usually not termed control flow statements. A set of statements is in turn generally structured as a block, which in addition to grouping, also defines a lexical scope. Interrupts and signals are low-level mechanisms that can alter the flow of control in a way similar to a subroutine, but usually occur as a response to some external stimulus or event (that can occur asynchronously), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breakpoint
In software development, a breakpoint is an intentional stopping or pausing place in a program, put in place for debugging purposes. It is also sometimes simply referred to as a pause. More generally, a breakpoint is a means of acquiring knowledge about a program during its execution. During the interruption, the programmer inspects the test environment (general purpose registers, memory, logs, files, etc.) to find out whether the program is functioning as expected. In practice, a breakpoint consists of one or more conditions that determine when a program's execution should be interrupted. Breakpoints were invented for ENIAC, one of the earliest digital computers, by programmer Betty Holberton. In the initial design of ENIAC, program flow was set by plugging cables from one unit to another. To make the program stop at a certain point, a cable was removed, called a ''breakpoint''. Machine breakpoints Early mainframe computers, such as the IBM/360, had console switches/dial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Datamation
''Datamation'' is a computer magazine that was published in print form in the United States between 1957 and 1998,Venerable IS Journal Shuts Down Sharon Machlis // ComputerWorld, page 15, 19 January 1998 and has since continued publication on the web. ''Datamation'' was previously owned by and acquired by TechnologyAdvice in 2020. Datamation is published as an online magazine at Datamation.com. History and profile When ''Datamation'' was first launched in 1957, it was not clear there would be a significant market for a computer magazine given how few |
GOTO
GoTo (goto, GOTO, GO TO or other case combinations, depending on the programming language) is a statement found in many computer programming languages. It performs a one-way transfer of control to another line of code; in contrast a function call normally returns control. The jumped-to locations are usually identified using labels, though some languages use line numbers. At the machine code level, a goto is a form of branch or jump statement, in some cases combined with a stack adjustment. Many languages support the goto statement, and many do not (see § language support). The structured program theorem proved that the goto statement is not necessary to write programs that can be expressed as flow charts; some combination of the three programming constructs of sequence, selection/choice, and repetition/iteration are sufficient for any computation that can be performed by a Turing machine, with the caveat that code duplication and additional variables may need to be introduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continuation
In computer science, a continuation is an abstract representation of the control state of a computer program. A continuation implements ( reifies) the program control state, i.e. the continuation is a data structure that represents the computational process at a given point in the process's execution; the created data structure can be accessed by the programming language, instead of being hidden in the runtime environment. Continuations are useful for encoding other control mechanisms in programming languages such as exceptions, generators, coroutines, and so on. The "current continuation" or "continuation of the computation step" is the continuation that, from the perspective of running code, would be derived from the current point in a program's execution. The term ''continuations'' can also be used to refer to first-class continuations, which are constructs that give a programming language the ability to save the execution state at any point and return to that point at a lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Go To Statement Considered Harmful
GoTo (goto, GOTO, GO TO or other case combinations, depending on the programming language) is a statement found in many computer programming languages. It performs a one-way transfer of control to another line of code; in contrast a function call normally returns control. The jumped-to locations are usually identified using labels, though some languages use line numbers. At the machine code level, a goto is a form of branch or jump statement, in some cases combined with a stack adjustment. Many languages support the goto statement, and many do not (see § language support). The structured program theorem proved that the goto statement is not necessary to write programs that can be expressed as flow charts; some combination of the three programming constructs of sequence, selection/choice, and repetition/iteration are sufficient for any computation that can be performed by a Turing machine, with the caveat that code duplication and additional variables may need to be introduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
INTERCAL
The Compiler Language With No Pronounceable Acronym (INTERCAL) is an esoteric programming language that was created as a parody by Don Woods and , two Princeton University students, in 1972. It satirizes aspects of the various programming languages at the time, as well as the proliferation of proposed language constructs and notations in the 1960s. There are two maintained implementations of INTERCAL dialects: C-INTERCAL (created in 1990), maintained by Eric S. Raymond and Alex Smith, and CLC-INTERCAL, maintained by Claudio Calvelli. History According to the original manual by the authors, The original Princeton implementation used punched cards and the EBCDIC character set. To allow INTERCAL to run on computers using ASCII, substitutions for two characters had to be made: $ substituted for ¢ as the ''mingle'' operator, "represent ngthe increasing cost of software in relation to hardware", and ? was substituted for ⊻ as the unary exclusive-or operator to "correctly expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intercal
The Compiler Language With No Pronounceable Acronym (INTERCAL) is an esoteric programming language that was created as a parody by Don Woods and , two Princeton University students, in 1972. It satirizes aspects of the various programming languages at the time, as well as the proliferation of proposed language constructs and notations in the 1960s. There are two maintained implementations of INTERCAL dialects: C-INTERCAL (created in 1990), maintained by Eric S. Raymond and Alex Smith, and CLC-INTERCAL, maintained by Claudio Calvelli. History According to the original manual by the authors, The original Princeton implementation used punched cards and the EBCDIC character set. To allow INTERCAL to run on computers using ASCII, substitutions for two characters had to be made: $ substituted for ¢ as the ''mingle'' operator, "represent ngthe increasing cost of software in relation to hardware", and ? was substituted for ⊻ as the unary exclusive-or operator to "correctly expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Action At A Distance (computer Science)
Action at a distance is an anti-pattern in computer science in which behavior in one part of a program varies wildly based on difficult or impossible to identify operations in another part of the program. The way to avoid the problems associated with action at a distance are a proper design, which avoids global variables and alters data only in a controlled and local manner, or usage of a pure functional programming style with referential transparency. The term is based on the concept of action at a distance in physics, which may refer to a process that allows objects to interact without a mediator particle such as the gluon. In particular, Albert Einstein referred to quantum nonlocality as "spooky action at a distance". Software bugs due to action at a distance may arise because a program component is doing something at the wrong time, or affecting something it should not. It is very difficult, however, to track down which component is responsible. Side effects from innoce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comment (computer Programming)
In computer programming, a comment is a programmer-readable explanation or ''annotation'' in the source code of a computer program. They are added with the purpose of making the source code easier for humans to understand, and are generally ignored by compilers and interpreters.Source code can be divided into ''program code'' (which consists of machine-translatable instructions); and ''comments'' (which include human-readable notes and other kinds of annotations in support of the program code). The syntax of comments in various programming languages varies considerably. Comments are sometimes also processed in various ways to generate documentation external to the source code itself by documentation generators, or used for integration with source code management systems and other kinds of external programming tools. The flexibility provided by comments allows for a wide degree of variability, but formal conventions for their use are commonly part of programming style guides. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruby (programming Language)
Ruby is an interpreted, high-level, general-purpose programming language which supports multiple programming paradigms. It was designed with an emphasis on programming productivity and simplicity. In Ruby, everything is an object, including primitive data types. It was developed in the mid-1990s by Yukihiro "Matz" Matsumoto in Japan. Ruby is dynamically typed and uses garbage collection and just-in-time compilation. It supports multiple programming paradigms, including procedural, object-oriented, and functional programming. According to the creator, Ruby was influenced by Perl, Smalltalk, Eiffel, Ada, BASIC, Java and Lisp. History Early concept Matsumoto has said that Ruby was conceived in 1993. In a 1999 post to the ''ruby-talk'' mailing list, he describes some of his early ideas about the language: Matsumoto describes the design of Ruby as being like a simple Lisp language at its core, with an object system like that of Smalltalk, blocks inspired by higher-o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> GOTO")
