翻訳と辞書 Words near each other ・ Commemorative coins of Austria ・ Commemorative coins of Bermuda ・ Commando Training Centre Royal Marines ・ Commando Training Wing ・ Commando VIP ・ Commandos (Afghanistan) ・ Commandos (album) ・ Commandos (film) ・ Commandos (series) ・ Commandos de Chasse ・ Commandos Marine ・ Commandos Strike at Dawn ・ Commandry (feudalism) ・ Commandry of Mirow ・ Commandry of Nemerow ・ Command–query separation ・ Commarin ・ Commatarcha ・ Commatarcha acidodes ・ Commatarcha characterias ・ Commatarcha chrysanches ・ Commatarcha citrogramma ・ Commatarcha oresbia ・ Commatarcha palaeosema ・ Commatarcha quaestrix ・ Commatarcha vaga ・ Commatica ・ Commatica acropelta ・ Commatica bifuscella ・ Commatica chionura Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Command–query separation ： ウィキペディア英語版 Command–query separation Command–query separation (CQS) is a principle of imperative computer programming. It was devised by Bertrand Meyer as part of his pioneering work on the Eiffel programming language. It states that every method should either be a ''command'' that performs an action, or a ''query'' that returns data to the caller, but not both. In other words, ''Asking a question should not change the answer''. More formally, methods should return a value only if they are referentially transparent and hence possess no side effects. ==Connection with design by contract== Command–query separation is particularly well suited to a design by contract (DbC) methodology, in which the design of a program is expressed as assertions embedded in the source code, describing the state of the program at certain critical times. In DbC, assertions are considered design annotations – not program logic – and as such, their execution should not affect the program state. CQS is beneficial to DbC because any value-returning method (any query) can be called by any assertion without fear of modifying program state. In theoretical terms, this establishes a measure of sanity, whereby one can reason about a program's state without simultaneously modifying that state. In practical terms, CQS allows all assertion checks to be bypassed in a working system to improve its performance without inadvertently modifying its behaviour. CQS may also prevent the occurrence of certain kinds of heisenbugs. 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「Command–query separation」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.