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Automatic Variable
In computer programming, an automatic variable is a local variable which is allocated and deallocated automatically when program flow enters and leaves the variable's scope. The scope is the lexical context, particularly the function or block in which a variable is defined. Local data is typically (in most languages) invisible outside the function or lexical context where it is defined. Local data is also invisible and inaccessible to a ''called'' function,unless it is a nested function, which itself is ''defined'' along that local data but is not deallocated, coming back in scope as the execution thread returns to the caller. Automatic local variables primarily applies to recursive lexically-scoped languages.although they exist in a somewhat similar, but not identical, form also in recursive languages with dynamic scoping, such as older variants of LISP Automatic local variables are normally allocated in the stack frame of the procedure in which they are declared.unless ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Type Inference
Type inference, sometimes called type reconstruction, refers to the automatic detection of the type of an expression in a formal language. These include programming languages and mathematical type systems, but also natural languages in some branches of computer science and linguistics. Nontechnical explanation In a typed language, a term's type determines the ways it can and cannot be used in that language. For example, consider the English language and terms that could fill in the blank in the phrase "sing _." The term "a song" is of singable type, so it could be placed in the blank to form a meaningful phrase: "sing a song." On the other hand, the term "a friend" does not have the singable type, so "sing a friend" is nonsense. At best it might be metaphor; bending type rules is a feature of poetic language. A term's type can also affect the interpretation of operations involving that term. For instance, "a song" is of composable type, so we interpret it as the thing created ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Local Variable
In computer science, a local variable is a variable that is given ''local scope''. A local variable reference in the function or block in which it is declared overrides the same variable name in the larger scope. In programming languages with only two levels of visibility, local variables are contrasted with global variables. On the other hand, many ALGOL-derived languages allow any number of nested levels of visibility, with private variables, functions, constants and types hidden within them, either by nested blocks or nested functions. Local variables are fundamental to procedural programming, and more generally modular programming: variables of local scope are used to avoid issues with side-effects that can occur with global variables. Scope Local variables may have a lexical or dynamic scope, though lexical (static) scoping is far more common. In lexical scoping (or lexical scope; also called static scoping or static scope), if a variable name's scope is a certain blo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Variable (computer Science)
In computer programming, a variable is an abstract storage location paired with an associated symbolic name, which contains some known or unknown quantity of data or object referred to as a '' value''; or in simpler terms, a variable is a named container for a particular set of bits or type of data (like integer, float, string, etc...). A variable can eventually be associated with or identified by a memory address. The variable name is the usual way to reference the stored value, in addition to referring to the variable itself, depending on the context. This separation of name and content allows the name to be used independently of the exact information it represents. The identifier in computer source code can be bound to a value during run time, and the value of the variable may thus change during the course of program execution. Variables in programming may not directly correspond to the concept of variables in mathematics. The latter is abstract, having no reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Memory Management
Memory management (also dynamic memory management, dynamic storage allocation, or dynamic memory allocation) is a form of Resource management (computing), resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. This is critical to any advanced computer system where more than a single Process (computing), process might be underway at any time. Several methods have been devised that increase the effectiveness of memory management. Virtual memory systems separate the memory addresses used by a process from actual physical addresses, allowing separation of processes and increasing the size of the virtual address space beyond the available amount of Random-access memory, RAM using paging or swapping to secondary storage. The quality of the virtual memory manager can have an extensive effect on overall system C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Object Lifetime
Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an aim, target, or objective * Object (grammar), a sentence element, such as a direct object or an indirect object Science, technology, and mathematics Computing * 3D model, a representation of a physical object * Object (computer science), a language mechanism for binding data with methods that operate on that data ** Object-orientation (other), in which concepts are represented as objects *** Object-oriented programming (OOP), in which an object is an instance of a class or array ** Object (IBM i), the fundamental unit of data storage in the IBM i operating system * Object file, the output of a compiler or other translator program (also known as "object code") * HTML object element Mathematics * Object (mathematics), an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
