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Lambda Lifting
Lambda lifting is a meta-process that restructures a computer program so that functions are defined independently of each other in a global scope. An individual ''lift'' transforms a local function (subroutine) into a global function. It is a two step process, consisting of: * Eliminating free variables in the function by adding parameters. * Moving functions from a restricted scope to broader or global scope. The term "lambda lifting" was first introduced by Thomas Johnsson around 1982 and was historically considered as a mechanism for implementing programming languages based on functional programming. It is used in conjunction with other techniques in some modern compilers. Lambda lifting is not the same as closure conversion. It requires all call sites to be adjusted (adding extra arguments (parameters) to calls) and does not introduce a closure for the lifted lambda expression. In contrast, closure conversion does not require call sites to be adjusted but does introduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Metaprogramming
Metaprogramming is a computer programming technique in which computer programs have the ability to treat other programs as their data. It means that a program can be designed to read, generate, analyse, or transform other programs, and even modify itself, while running. In some cases, this allows programmers to minimize the number of lines of code to express a solution, in turn reducing development time. It also allows programs more flexibility to efficiently handle new situations with no recompiling. Metaprogramming can be used to move computations from runtime to compile time, to generate code using compile time computations, and to enable self-modifying code. The ability of a programming language to be its own metalanguage allows reflective programming, and is termed ''reflection''. Reflection is a valuable language feature to facilitate metaprogramming. Metaprogramming was popular in the 1970s and 1980s using list processing languages such as Lisp. Lisp machine hardware ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Beta Reduction
In mathematical logic, the lambda calculus (also written as ''λ''-calculus) is a formal system for expressing computation based on function abstraction and application using variable Name binding, binding and Substitution (algebra), substitution. Untyped lambda calculus, the topic of this article, is a universal machine, a model of computation that can be used to simulate any Turing machine (and vice versa). It was introduced by the mathematician Alonzo Church in the 1930s as part of his research into the foundations of mathematics. In 1936, Church found a formulation which was #History, logically consistent, and documented it in 1940. Lambda calculus consists of constructing #Lambda terms, lambda terms and performing #Reduction, reduction operations on them. A term is defined as any valid lambda calculus expression. In the simplest form of lambda calculus, terms are built using only the following rules: # x: A #validLambdaVar, variable is a character or string representing a pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |