blocks|key|1908779|text|以下是该规范对lexical+environments的描述|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1908780|1908781|词法环境是一种规范类型，用于根据ECMAScript代码的词法嵌套结构定义，即标识符与特定变量和函数的关联。Lexical+Environment由一个Environment记录和一个可能为空的外部Lexical+Environment引用组成。|blockquote|style|BOLD|1908782|1908783|1908784|基于这一点，我会说是的，这就是人们在说“作用域”时通常谈论的。|1908785|尽管可能会争论“作用域”实际上被定义为"Declarative+Environment+Record"：|1908786|1908787|每个声明性环境记录都与一个包含变量和/或函数声明的ECMAScript程序范围相关联。声明性环境记录绑定由其作用域中包含的声明定义的标识符集。|1908788|1908789|1908790|如果你认为“作用域”是一个包含标识符和值之间绑定的东西，那么第二个定义可能更合适。如果你认为它是知道它的祖先作用域的东西，那么第一个定义更合适。|1908791|编辑:第三个选项是"Execution+Context“。|1908792|entityMap|0|LINK|mutability|MUTABLE|url|http://es5.github.com/#x10.2|1|http://es5.github.com/#x10.2.1.1|2|http://es5.github.com/#x10.3^0|7|K|0|0|0|11|D|0|0|0|0|K|U|1|0|0|0|0|0|0|A|H|2|0^^$0|@$1|2|3|4|5|6|7|1A|8|@]|9|@$A|1B|B|1C|1|1D]]|C|$]]|$1|D|3|-4|5|6|7|1E|8|@]|9|@]|C|$]]|$1|E|3|F|5|G|7|1F|8|@$A|1G|B|1H|H|I]]|9|@]|C|$]]|$1|J|3|-4|5|6|7|1I|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|1J|8|@]|9|@]|C|$]]|$1|L|3|M|5|6|7|1K|8|@]|9|@]|C|$]]|$1|N|3|O|5|6|7|1L|8|@]|9|@$A|1M|B|1N|1|1O]]|C|$]]|$1|P|3|-4|5|6|7|1P|8|@]|9|@]|C|$]]|$1|Q|3|R|5|G|7|1Q|8|@]|9|@]|C|$]]|$1|S|3|-4|5|6|7|1R|8|@]|9|@]|C|$]]|$1|T|3|-4|5|6|7|1S|8|@]|9|@]|C|$]]|$1|U|3|V|5|6|7|1T|8|@]|9|@]|C|$]]|$1|W|3|X|5|6|7|1U|8|@]|9|@$A|1V|B|1W|1|1X]]|C|$]]|$1|Y|3|-4|5|6|7|1Y|8|@]|9|@]|C|$]]]|Z|$10|$5|11|12|13|C|$14|15]]|16|$5|11|12|13|C|$14|17]]|18|$5|11|12|13|C|$14|19]]]]

Here's what the spec says about <a href="http://es5.github.com/#x10.2" rel="noreferrer">lexical environments</a>:

<blockquote>
 A Lexical Environment is a specification type used to define the association of Identifiers to specific variables and functions based upon the lexical nesting structure of ECMAScript code. A Lexical Environment consists of an Environment Record and a possibly null reference to an outer Lexical Environment.
</blockquote>

Based on that, I would say yes, that's what people are usually talking about when they say "scope".

Although it could probably be argued that a "scope" is actually defined as a "<a href="http://es5.github.com/#x10.2.1.1" rel="noreferrer">Declarative Environment Record</a>":

<blockquote>
 Each declarative environment record is associated with an ECMAScript program scope containing variable and/or function declarations. A declarative environment record binds the set of identifiers defined by the declarations contained within its scope.
</blockquote>

If you think of a "scope" as a thing that contains bindings between identifiers and values, then the 2nd definition probably fits better. If you think of it as something that is aware of its ancestor scopes, then the first definition fits better.

Edit: and a third option is "<a href="http://es5.github.com/#x10.3" rel="noreferrer">Execution Context</a>".

blocks|key|1908794|text|词法环境是编写函数的环境。也就是说，它所处的静态顺序/位置，而不管它是从哪里调用的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908795|变量/函数的作用域基本上是变量可见/可访问的位置。|1908796|执行上下文是指运行时期间任意时刻的执行堆栈的状态。这就是当前的执行上下文。|1908797|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

Lexical Environment is the environment of the function where it is written. That is, the static order/place where it is situated, regardless from where it is called from.

Scope of a variable/function is basically the locations from where a variable is visible/accessible.

Execution context is the status of the execution stack at any point during runtime. That is the current execution context.

blocks|key|1908804|text|根据我刚刚从“Javascript忍者的秘密，2/e”中学到的东西，给出了答案--|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1908805|它们是不同的概念，但又是相关的，我们需要定义一个相关的概念-堆栈执行上下文&它是堆栈来理解。|1908806|Execution+Context+&+Execution+Context+stack：Execution+context是跟踪函数或全局代码执行的内部javascript构造。js引擎维护一个堆栈数据结构-执行上下文堆栈或调用堆栈，其中包含这些上下文，并且全局执行上下文位于该堆栈的底部。并且当函数开始执行时，创建新的执行上下文并将其推送到堆栈。特定的执行上下文跟踪正在执行相应函数的语句的指针。当相应函数的执行完成时，从堆栈中弹出执行上下文。|offset|length|style|BOLD|1908807|词法环境：它是保存标识符-变量映射的内部js引擎构造。(这里标识符是指变量/函数的名称，变量是对包含函数类型对象或原始值的实际对象的引用)。词法环境还包含对父词法环境的引用。|1908808|现在，对于每个执行上下文+--+1)创建相应的词法环境，并且2)如果在该执行上下文中创建了任何函数，则在该函数的内部属性()处存储对该词法环境的引用。因此，每个函数都会跟踪与创建它的执行上下文相关的词法环境。|1908809|每个词法环境跟踪其父词法环境(父执行上下文的词法环境)。因此，每个函数都有一系列附加在其上的词汇环境。注意:在js中，函数是一个对象，通过语句创建一个函数就意味着创建一个函数类型的对象。因此，与其他对象一样，函数可以包含内部和用户定义的属性|1908810|Scope：它是一个与语言无关的概念，指的是变量或函数对执行代码的可见性。在js中，如果变量或函数存在于当前词法环境或封闭函数的词法环境链中，则该变量或函数对执行代码是可见的。在全局代码的情况下，链不存在。|1908811|希望，你现在明白了..。|1908812|注意:与函数的情况类似，通过在es6中引入let和const，当一个块开始执行时(if块，for+loop块等)，还会创建一个新的词法环境，将父函数的词法环境作为父函数。|1908813|entityMap^0|0|0|0|H|K|N|18|H|2W|7|34|4|3L|7|0|0|4|9|8|U|3|18|2|26|5|0|7|5|G|19|0|0|0|5|0|0|L|9|15|2|19|8|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Y|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Z|8|@$F|10|G|11|H|I]|$F|12|G|13|H|I]|$F|14|G|15|H|I]|$F|16|G|17|H|I]|$F|18|G|19|H|I]|$F|1A|G|1B|H|I]]|9|@]|A|$]]|$1|J|3|K|5|6|7|1C|8|@$F|1D|G|1E|H|I]|$F|1F|G|1G|H|I]|$F|1H|G|1I|H|I]|$F|1J|G|1K|H|I]|$F|1L|G|1M|H|I]]|9|@]|A|$]]|$1|L|3|M|5|6|7|1N|8|@$F|1O|G|1P|H|I]|$F|1Q|G|1R|H|I]]|9|@]|A|$]]|$1|N|3|O|5|6|7|1S|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|1T|8|@$F|1U|G|1V|H|I]]|9|@]|A|$]]|$1|R|3|S|5|6|7|1W|8|@]|9|@]|A|$]]|$1|T|3|U|5|6|7|1X|8|@$F|1Y|G|1Z|H|I]|$F|20|G|21|H|I]|$F|22|G|23|H|I]]|9|@]|A|$]]|$1|V|3|-4|5|6|7|24|8|@]|9|@]|A|$]]]|W|$]]

Giving the answer based on what I have just learned from 'Secrets of the Javascript Ninja, 2/e' --

They are different concepts but related, we need to define a related concept - Execution Context &amp; it's stack to understand.

Execution Context &amp; Execution Context stack : Execution context is the internal javascript construct to track execution of a function or the global code. The js engine maintains a stack data structure - execution context stack or call stack, which contains these contexts and the global execution context stays at the bottom of this stack. And a new execution context is created and pushed to the stack when execution of a function begins. A particular execution context tracks the pointer where statement of the corresponding function is being executed. An execution context is popped from the stack when corresponding function's execution is finished.

Lexical Environment : it's the internal js engine construct that holds identifier-variable mapping. (here identifier refers to the name of variables/functions, and variable is the reference to actual object [including function type object] or primitive value). A lexical environment also holds a reference to a parent lexical environment. 

Now, for every execution context -- 1) a corresponding lexical environment is created and 2) if any function is created in that execution context, reference to that lexical environment is stored at the internal property ( [[Environment]] ) of that function. So, every function tracks the lexical environment related to the execution context it was created in. 

And every lexical environment tracks its parent lexical environment (that of parent execution context). As a result, every function has a chain of lexical environments attached to it. [Note: in js a function is an object, creating a function by a statement means creating an object of type Function. So like other objects, a function can hold properties both internal and user defined]

Scope : it's the language agnostic concept, to refer to the visibility of variables or functions to the executing code. In js a variable or function is visible to the executing code, if it is there in the current lexical environment or in the lexical-environment-chain of the enclosing function. In case of global code, the chain does not exist.

Hope, you understand now .. 

Note: similar to function's case, by the introduction of let and const in es6, when a block begins to execute (if block, for loop block etc), a new lexical environment is also created having the parent function's lexical environment as parent.

Is lexical environment and scope in javascript one and the same thing?

Lexical environment and function scope

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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