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Lua ( , from (ポルトガル語:lua) (:ˈlu.(w)ɐ) meaning ''moon'') is a lightweight multi-paradigm programming language designed primarily for embedded systems and clients. Lua is cross-platform since it is written in ANSI C,〔(【引用サイトリンク】 About Lua )〕 and has a relatively simple C API. Lua was originally designed in 1993 as a language for extending software applications to meet the increasing demand for customization at the time. It provided the basic facilities of most procedural programming languages, but more complicated or domain-specific features were not included; rather, it included mechanisms for extending the language, allowing programmers to implement such features. As Lua was intended to be a general embeddable extension language, the designers of Lua focused on improving its speed, portability, extensibility, and ease-of-use in development. The Lua compiler for version 5.3.1 was built from approximately 23,000 lines of code.〔〔 == History == Lua was created in 1993 by Roberto Ierusalimschy, Luiz Henrique de Figueiredo, and Waldemar Celes, members of the Computer Graphics Technology Group (Tecgraf) at the Pontifical Catholic University of Rio de Janeiro, in Brazil. From 1977 until 1992, Brazil had a policy of strong trade barriers (called a market reserve) for computer hardware and software. In that atmosphere, Tecgraf's clients could not afford, either politically or financially, to buy customized software from abroad. Those reasons led Tecgraf to implement the basic tools it needed from scratch. Lua's historical "father and mother" were the data-description/configuration languages ''SOL'' (Simple Object Language) and ''DEL'' (data-entry language).〔(【引用サイトリンク】The evolution of an extension language: a history of Lua ) 〕 They had been independently developed at Tecgraf in 1992–1993 to add some flexibility into two different projects (both were interactive graphical programs for engineering applications at Petrobras company). There was a lack of any flow-control structures in SOL and DEL, and Petrobras felt a growing need to add full programming power to them. As the language's authors wrote, in ''The Evolution of Lua'': Lua 1.0 was designed in such a way that its object constructors, being then slightly different from the current light and flexible style, incorporated the data-description syntax of SOL (hence the name Lua – ''sol'' is Portuguese for sun; ''lua'' is moon). Lua syntax for control structures was mostly borrowed from Modula (if, while, repeat/until), but also had taken influence from CLU (multiple assignments and multiple returns from function calls, as a simpler alternative to reference parameters or explicit pointers), C++ ("neat idea of allowing a local variable to be declared only where we need it"〔), SNOBOL and AWK (associative arrays). In an article published in ''Dr. Dobb's Journal'', Lua's creators also state that LISP and Scheme with their single, ubiquitous data structure mechanism (the list) were a major influence on their decision to develop the table as the primary data structure of Lua. Lua semantics have been increasingly influenced by Scheme over time,〔 especially with the introduction of anonymous functions and full lexical scoping. Versions of Lua prior to version 5.0 were released under a license similar to the BSD license. From version 5.0 onwards, Lua has been licensed under the MIT License. Both are permissive free software licences and are almost identical. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lua (programming language)」の詳細全文を読む スポンサード リンク
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