| TECH |
Engadget Japanese |
2020年1月17日、GPS搭載のスマートバンド「HUAWEI Band 4 Pro」が発売されました：今日は何の日？ |
https://japanese.engadget.com/today-203023351.html
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huaweibandpro |
2022-01-16 20:30:23 |
| 海外TECH |
DEV Community |
Advanced JavaScript Series - Part 4.2: Scope Chains and their working, Lexical and Variable Environments |
https://dev.to/pranav016/advanced-javascript-series-part-42-scope-chains-and-their-working-lexical-and-variable-environments-19d5
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Advanced JavaScript Series Part Scope Chains and their working Lexical and Variable Environments What is a Scope Chain The Scope Chain is the hierarchy of scopes that will be searched in order to find a function or variable Credits Anuradha AggarwalWhen a variable is used in JavaScript the JavaScript engine will try to find the variable s value in the current scope If it could not find the variable it will look into the outer scope and will continue to do so until it finds the variable or reaches global scope If it s still could not find the variable it will either implicitly declare the variable in the global scope if not in strict mode or return an error The Scope Chain is used to resolve variables When asked to resolve a variable JavaScript always starts at the innermost level of the code nest and keeps jumping back to the parent scope until it finds the variable or any other resource it is looking for The scope chain can simply be defined as an object that contains a bunch of other objects Each object has the variable to value mapping for its particular execution context Example Code let c function a let b console log Inside function a a Sample Scope chain object for the function a functionLexicalEnvironment environmentRecord b outer c Lexical Environment A lexical environment is a structure that holds identifier variable mapping here identifier refers to the name of variables functions and the variable is the reference to actual object including function object and array object or primitive value Simply put a lexical environment is a place where variables and references to the objects are stored A lexical environment conceptually looks like this lexicalEnvironment environmentRecord lt identifier gt lt value gt lt identifier gt lt value gt outer lt Reference to the parent lexical environment gt Let s understand this with the help of an example let language JS function a let b console log Inside function a a console log Inside global execution context The JavaScript engine creates a new lexical environment to store the variables and functions defined in the global scope when it establishes a global execution context to execute global code As a result the lexical environment for the global scope will be as follows globalLexicalEnvironment environmentRecord language JS a lt reference to function object gt outer null Because there is no outer lexical environment for the global scope the outer lexical environment is set to null When the engine establishes an execution context for the a function it also creates a lexical environment in which variables defined in the function can be stored while the function is being executed As a result the function s lexical environment will look like this functionLexicalEnvironment environmentRecord b outer lt globalLexicalEnvironment gt Because the function is surrounded by the global scope in the source code the function s outer lexical environment is set to the global lexical environment When a function finishes executing its execution context is removed from the stack but its lexical environment may or may not be erased from memory depending on whether it is referenced by any other lexical environments in their outer lexical environment property Variable Environment The variable environment is a representation of the lexical environment s local memory In the environment record the lexical environment stores variables as well as other information such as the infamous this We ve previously used one variable environment the global environment s memory which holds variables that are universally available throughout the script While the lexical environment refers to this global environment the variable environment only refers to variables created within the scope of the provided function within the lexical environment The variable environment maps the local scope of a given environment In other words the variable environment stores those variables defined within the given working code block Credits Benjamin Gruenbaum Appendix Advanced JavaScript Series Part Behind the scenes JavaScript Engine ATS Hidden Classes Garbage Collection Advanced JavaScript Series Part Execution Context and Call StackAdvanced JavaScript Series Part Weird JS behavior Strict Mode and Hoisting Temporal Dead ZoneAdvanced JavaScript Series Part Global Function and Block Scope Lexical vs Dynamic Scoping References bdov javascript typescript execution vs lexical vs variable environment fff |
2022-01-16 20:25:36 |
| Apple |
AppleInsider - Frontpage News |
Apple once prototyped HomePod with battery power |
https://appleinsider.com/articles/22/01/16/apple-once-prototyped-homepod-with-battery-power?utm_medium=rss
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Apple once prototyped HomePod with battery powerApple allegedly thought about creating a portable version of the HomePod with a battery with a report claiming a prototype was produced but not turned into a final product A HomePod mini and a USB C battery pack Both the HomePod and the HomePod mini are designed for use indoors with each equipped with power cables and to be plugged into an outlet While Apple doesn t currently sell a portable version it did once consider the possibility Read more |
2022-01-16 20:09:55 |
| 海外TECH |
Engadget |
Safari exploit can leak browser histories and Google account info |
https://www.engadget.com/safari-webkit-exploit-browser-history-google-account-200711732.html?src=rss
|
Safari exploit can leak browser histories and Google account infoApple device users appear to be vulnerable to a significant browser privacy flaw According to toMac FingerprintJS has disclosed an exploit that lets attackers obtain your recent browser history and even some Google account info from Safari across all supported platforms as well as third party browsers on iOS and iPadOS The IndexedDB framework used to store data on many browsers is violating the quot same origin quot policy that prevents documents and scripts from one location such as a domain or protocol from interacting with content from another letting appropriately coded websites deduce Google info from signed in users as well as histories from open tabs and windows The flaw only compromises the names of the databases rather than the content itself However this would still be enough for a malicious site owner to grab your Google username discover your profile picture and otherwise learn more about you The history could also be used to piece together a rudimentary profile of the sites you like Private browsing won t defeat the exploit FingerprintJS said We ve asked Apple for comment FingerprintJS said it reported the issue on November th however and that Apple hadn t yet addressed it with security patches honoring same origin policy Until then the only solution may be to either use a third party browser on Macs or block all JavaScript neither of which is necessarily an option |
2022-01-16 20:07:11 |
| ニュース |
BBC News - Home |
Pacific volcano: New Zealand sends flight to assess Tonga damage |
https://www.bbc.co.uk/news/world-asia-60009944?at_medium=RSS&at_campaign=KARANGA
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tonga |
2022-01-16 20:37:28 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
資源高騰で企業の7割が経営に打撃でも「値上げできない」切実な理由【上場50社緊急調査】 - 企業悶絶！インフレ襲来 |
https://diamond.jp/articles/-/293087
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日本企業 |
2022-01-17 05:25:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
パナソニック、トヨタも苦悩、鋼材高より怖い「2つの金属」高騰に自動車電機メーカー悶絶 - 企業悶絶！インフレ襲来 |
https://diamond.jp/articles/-/293086
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世界経済 |
2022-01-17 05:20:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
みずほの木原次期社長の脇を固めるキーマン、平成入行の「4人衆」とは - Diamond Premium News |
https://diamond.jp/articles/-/293401
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みずほの木原次期社長の脇を固めるキーマン、平成入行の「人衆」とはDiamondPremiumNewsみずほフィナンシャルグループが、坂井辰史社長の後任として木原正裕執行役を昇格させるとともに、今年月で退任する佐藤康博会長の後任に今井誠司副社長を充てる方針を固めた。 |
2022-01-17 05:17:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
ソニーだけが高笑い！血税4000億円で誘致した半導体TSMC熊本工場の「大矛盾」 - 戦略物資 半導体＆EV電池 |
https://diamond.jp/articles/-/293258
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不都合な真実 |
2022-01-17 05:15:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
レアアースは2022年「3割高」でショック再来！資源確保で日本が打てる手は - 総予測2022 |
https://diamond.jp/articles/-/291222
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中村繁夫 |
2022-01-17 05:10:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
「山口銀行のクーデターは恒例行事」、前CEO解任劇を巡る山口FGの“3つの誤算” - 銀行クーデター |
https://diamond.jp/articles/-/293237
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山口フィナンシャルグループ |
2022-01-17 05:05:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
危機の時代のリーダーは 明日をつくり、今日を戦う - DQ |
https://diamond.jp/articles/-/291679
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|
2022-01-17 05:03:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
POWERING GOODで 社会イノベーションを加速する - DQ |
https://diamond.jp/articles/-/291461
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|
2022-01-17 05:02:00 |
| ビジネス |
ダイヤモンド・オンライン - 新着記事 |
原点回帰、自由と規律、 集合知のイノベーション - DQ |
https://diamond.jp/articles/-/291422
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|
2022-01-17 05:01:00 |
| ビジネス |
電通報 | 広告業界動向とマーケティングのコラム・ニュース |
「＃剃るに自由を」に託した、貝印の思いとは？～第74回広告電通賞 SDGs特別賞受賞記念対談 |
https://dentsu-ho.com/articles/8041
|
広告電通賞 |
2022-01-17 06:00:00 |
| 北海道 |
北海道新聞 |
＜社説＞噴火後の津波 未知の現象解明が急務 |
https://www.hokkaido-np.co.jp/article/634088/
|
南太平洋 |
2022-01-17 05:05:00 |
| 北海道 |
北海道新聞 |
特急１７日正常化 ＪＲ北海道 |
https://www.hokkaido-np.co.jp/article/634102/
|
除雪作業 |
2022-01-17 05:01:05 |
| ビジネス |
東洋経済オンライン |
アシックス､｢米国での大失敗｣から学んだ教訓 カジュアル路線を転換し､原点の｢走る｣へ回帰 | 専門店･ブランド･消費財 | 東洋経済オンライン |
https://toyokeizai.net/articles/-/503227?utm_source=rss&utm_medium=http&utm_campaign=link_back
|
学んだ教訓 |
2022-01-17 06:00:00 |
| ビジネス |
東洋経済オンライン |
最新！これが｢借金の多い企業｣トップ500社だ 今年も1位はソフトバンクグループに | 企業ランキング | 東洋経済オンライン |
https://toyokeizai.net/articles/-/503159?utm_source=rss&utm_medium=http&utm_campaign=link_back
|
東洋経済オンライン |
2022-01-17 05:40:00 |
| ビジネス |
東洋経済オンライン |
関電と提携､｢CO2排出を可視化｣する黒子の素顔 電力会社や大手銀行と提携､脱炭素支える裏方 | 資源・エネルギー | 東洋経済オンライン |
https://toyokeizai.net/articles/-/503229?utm_source=rss&utm_medium=http&utm_campaign=link_back
|
大手銀行 |
2022-01-17 05:20:00 |
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