blocks|key|822771|text|因为咖啡脚本会编译成JavaScript，所以您可以拥有私有变量的惟一方式就是通过闭包。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|822772|class+Animal
++foo+=+2+#+declare+it+inside+the+class+so+all+prototypes+share+it+through+closure
++constructor:+(value)+->
++++++foo+=+value

++test:+(meters)+->
++++alert+foo

e+=+new+Animal(5);
e.test()+#+5|code-block|syntax|javascript|822773|这将通过以下JavaScript向下编译：|822774|var+Animal,+e;
Animal+=+(function()+{
++var+foo;+//+closured+by+test+and+the+constructor
++foo+=+2;
++function+Animal(value)+{
++++foo+=+value;
++}
++Animal.prototype.test+=+function(meters)+{
++++return+alert(foo);
++};
++return+Animal;
})();

e+=+new+Animal(5);
e.test();+//+5|822775|当然，这与通过使用闭包可以拥有的所有其他私有变量具有相同的限制，例如，新添加的方法无法访问它们，因为它们不是在相同的作用域中定义的。|822776|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Since coffee script compiles down to JavaScript the only way you can have private variables is through closures.

<pre><code>class Animal
 foo = 2 # declare it inside the class so all prototypes share it through closure
 constructor: (value) -&gt;
 foo = value

 test: (meters) -&gt;
 alert foo

e = new Animal(5);
e.test() # 5
</code></pre>

This will compile down through the following JavaScript:

<pre><code>var Animal, e;
Animal = (function() {
 var foo; // closured by test and the constructor
 foo = 2;
 function Animal(value) {
 foo = value;
 }
 Animal.prototype.test = function(meters) {
 return alert(foo);
 };
 return Animal;
})();

e = new Animal(5);
e.test(); // 5
</code></pre>

Of course this has all the same limitations as all the other private variables you can have through the use of closures, for example, newly added methods don't have access to them since they were not defined in the same scope.

blocks|key|822799|text|类只是函数，所以它们创建作用域。在这个作用域中定义的所有内容从外部都是不可见的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|822800|class+Foo
++#+this+will+be+our+private+method.+it+is+invisible
++#+outside+of+the+current+scope
++foo+=+->+"foo"

++#+this+will+be+our+public+method.
++#+note+that+it+is+defined+with+':'+and+not+'='
++#+'='+creates+a+*local*+variable
++#+:+adds+a+property+to+the+class+prototype
++bar:+->+foo()

c+=+new+Foo

#+this+will+return+"foo"
c.bar()

#+this+will+crash
c.foo|code-block|syntax|javascript|822801|coffeescript将其编译为以下代码：|822802|(function()+{
++var+Foo,+c;

++Foo+=+(function()+{
++++var+foo;

++++function+Foo()+{}

++++foo+=+function()+{
++++++return+"foo";
++++};

++++Foo.prototype.bar+=+function()+{
++++++return+foo();
++++};

++++return+Foo;

++})();

++c+=+new+Foo;

++c.bar();

++c.foo();

}).call(this);|822803|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

classes are just functions so they create scopes. everything defined inside this scope won't be visible from the outside.

<pre><code>class Foo
 # this will be our private method. it is invisible
 # outside of the current scope
 foo = -&gt; "foo"

 # this will be our public method.
 # note that it is defined with ':' and not '='
 # '=' creates a *local* variable
 # : adds a property to the class prototype
 bar: -&gt; foo()

c = new Foo

# this will return "foo"
c.bar()

# this will crash
c.foo
</code></pre>

coffeescript compiles this into the following:

<pre><code>(function() {
 var Foo, c;

 Foo = (function() {
 var foo;

 function Foo() {}

 foo = function() {
 return "foo";
 };

 Foo.prototype.bar = function() {
 return foo();
 };

 return Foo;

 })();

 c = new Foo;

 c.bar();

 c.foo();

}).call(this);
</code></pre>

blocks|key|822851|text|我想展示一些更花哨的东西|type|unstyled|depth|inlineStyleRanges|entityRanges|data|822852|class+Thing+extends+EventEmitter
++constructor:+(+nm)+->
++++_name+=+nm
++++Object.defineProperty+@,+'name',
++++++get:+->
++++++++_name
++++++set:+(val)+->
++++++++_name+=+val
++++++enumerable:+true
++++++configurable:+true|code-block|syntax|javascript|822853|现在你可以做|822854|t+=+new+Thing(+'Dropin')
#++members+can+be+accessed+like+properties+with+the+protection+from+getter/setter+functions!
t.name+=+'Dragout'++
console.log+t.name
#+no+way+to+access+the+private+member
console.log+t._name|822855|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I'd like to show something even fancier 

<pre><code>class Thing extends EventEmitter
 constructor: ( nm) -&gt;
 _name = nm
 Object.defineProperty @, 'name',
 get: -&gt;
 _name
 set: (val) -&gt;
 _name = val
 enumerable: true
 configurable: true
</code></pre>

Now you can do

<pre><code>t = new Thing( 'Dropin')
# members can be accessed like properties with the protection from getter/setter functions!
t.name = 'Dragout' 
console.log t.name
# no way to access the private member
console.log t._name
</code></pre>

blocks|key|1037890|text|如果只想将私有成员与公共成员分开，只需将其包装在$+variable中即可|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1037891|$:
++++++++requirements:
++++++++++++++{}
++++++++body:+null
++++++++definitions:+null|code-block|syntax|javascript|1037892|并使用@$.requirements|offset|length|style|CODE|1037893|entityMap^0|0|0|3|F|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

If you want only separate private memebers from public, just wrap it in $ variable

<pre><code>$:
 requirements:
 {}
 body: null
 definitions: null
</code></pre>

and use <code>@$.requirements</code>

blocks|key|822944|text|下面是如何在Coffeescript中声明私有的非静态成员|type|unstyled|depth|inlineStyleRanges|entityRanges|data|822945|要获得完整的参考资料，您可以查看https://github.com/vhmh2005/jsClass|offset|length|822946|class+Class

++#+private+members
++#+note:+'='+is+used+to+define+private+members
++#+naming+convention+for+private+members+is+_camelCase

++_privateProperty+=+0

++_privateMethod+=+(value)+->++++++++
++++_privateProperty+=+value
++++return

++#+example+of+_privateProperty+set+up+in+class+constructor
++constructor:+(privateProperty,+@publicProperty)+->
++++_privateProperty+=+privateProperty|code-block|syntax|javascript|822947|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/vhmh2005/jsClass^0|0|G|Z|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@$D|U|E|V|1|W]]|A|$]]|$1|F|3|G|5|H|7|X|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

Here is how you can declare private, non-static members in Coffeescript 
For full reference, you can take a look at <a href="https://github.com/vhmh2005/jsClass" rel="nofollow">https://github.com/vhmh2005/jsClass</a>

<pre><code>class Class

 # private members
 # note: '=' is used to define private members
 # naming convention for private members is _camelCase

 _privateProperty = 0

 _privateMethod = (value) -&gt; 
 _privateProperty = value
 return

 # example of _privateProperty set up in class constructor
 constructor: (privateProperty, @publicProperty) -&gt;
 _privateProperty = privateProperty
</code></pre>

blocks|key|1037980|text|这里有一个解决方案，它借鉴了这里的几个其他答案以及https://stackoverflow.com/a/7579956/1484513。它将私有实例(非静态)变量存储在私有类(静态)数组中，并使用对象ID来知道该数组的哪个元素包含属于每个实例的数据。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1037981|#+Add+IDs+to+classes.
(->
++i+=+1
++Object.defineProperty+Object.prototype,+"__id",+{+writable:true+}
++Object.defineProperty+Object.prototype,+"_id",+{+get:+->+@__id+?=+i%2B%2B+}
)()

class+MyClass
++#+Private+attribute+storage.
++__+=+[]

++#+Private+class+(static)+variables.
++_a+=+null
++_b+=+null

++#+Public+instance+attributes.
++c:+null

++#+Private+functions.
++_getA+=+->+a

++#+Public+methods.
++getB:+->+_b
++getD:+->+__[@._id].d

++constructor:+(a,b,@c,d)+->
++++_a+=+a
++++_b+=+b

++++#+Private+instance+attributes.
++++__[@._id]+=+{d:d}

#+Test

test1+=+new+MyClass+'s',+'t',+'u',+'v'
console.log+'test1',+test1.getB(),+test1.c,+test1.getD()++#+test1+t+u+v

test2+=+new+MyClass+'W',+'X',+'Y',+'Z'
console.log+'test2',+test2.getB(),+test2.c,+test2.getD()++#+test2+X+Y+Z

console.log+'test1',+test1.getB(),+test1.c,+test1.getD()++#+test1+X+u+v

console.log+test1.a+++++++++#+undefined
console.log+test1._a++++++++#+undefined

#+Test+sub-classes.

class+AnotherClass+extends+MyClass

test1+=+new+AnotherClass+'s',+'t',+'u',+'v'
console.log+'test1',+test1.getB(),+test1.c,+test1.getD()++#+test1+t+u+v

test2+=+new+AnotherClass+'W',+'X',+'Y',+'Z'
console.log+'test2',+test2.getB(),+test2.c,+test2.getD()++#+test2+X+Y+Z

console.log+'test1',+test1.getB(),+test1.c,+test1.getD()++#+test1+X+u+v

console.log+test1.a+++++++++#+undefined
console.log+test1._a++++++++#+undefined
console.log+test1.getA()++++#+fatal+error|code-block|syntax|javascript|1037982|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/7579956/1484513^0|P|17|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Here is a solution that draws on several of the other answers here plus <a href="https://stackoverflow.com/a/7579956/1484513">https://stackoverflow.com/a/7579956/1484513</a>. It stores the private instance (non-static) variables in a private class (static) array and uses an object ID to know which element of that array contains the data belonging to each instance.

<pre><code># Add IDs to classes.
(-&gt;
 i = 1
 Object.defineProperty Object.prototype, "__id", { writable:true }
 Object.defineProperty Object.prototype, "_id", { get: -&gt; @__id ?= i++ }
)()

class MyClass
 # Private attribute storage.
 __ = []

 # Private class (static) variables.
 _a = null
 _b = null

 # Public instance attributes.
 c: null

 # Private functions.
 _getA = -&gt; a

 # Public methods.
 getB: -&gt; _b
 getD: -&gt; __[@._id].d

 constructor: (a,b,@c,d) -&gt;
 _a = a
 _b = b

 # Private instance attributes.
 __[@._id] = {d:d}

# Test

test1 = new MyClass 's', 't', 'u', 'v'
console.log 'test1', test1.getB(), test1.c, test1.getD() # test1 t u v

test2 = new MyClass 'W', 'X', 'Y', 'Z'
console.log 'test2', test2.getB(), test2.c, test2.getD() # test2 X Y Z

console.log 'test1', test1.getB(), test1.c, test1.getD() # test1 X u v

console.log test1.a # undefined
console.log test1._a # undefined

# Test sub-classes.

class AnotherClass extends MyClass

test1 = new AnotherClass 's', 't', 'u', 'v'
console.log 'test1', test1.getB(), test1.c, test1.getD() # test1 t u v

test2 = new AnotherClass 'W', 'X', 'Y', 'Z'
console.log 'test2', test2.getB(), test2.c, test2.getD() # test2 X Y Z

console.log 'test1', test1.getB(), test1.c, test1.getD() # test1 X u v

console.log test1.a # undefined
console.log test1._a # undefined
console.log test1.getA() # fatal error
</code></pre>

blocks|key|1038043|text|咖啡脚本中的"class“会导致基于原型的结果。因此，即使您使用私有变量，它也是在实例之间共享的。您可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1038044|EventEmitter+=+->
++privateName+=+""

++setName:+(name)+->+privateName+=+name
++getName:+->+privateName|code-block|syntax|javascript|1038045|。。通向|1038046|emitter1+=+new+EventEmitter()
emitter1.setName+'Name1'

emitter2+=+new+EventEmitter()
emitter2.setName+'Name2'

console.log+emitter1.getName()+#+'Name1'
console.log+emitter2.getName()+#+'Name2'|1038047|但是要注意将私有成员放在公共函数之前，因为咖啡脚本将公共函数作为对象返回。看看编译后的Javascript：|1038048|EventEmitter+=+function()+{
++var+privateName+=+"";

++return+{
++++setName:+function(name)+{
++++++return+privateName+=+name;
++++},
++++getName:+function()+{
++++++return+privateName;
++++}
++};
};|1038049|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

"class" in coffee scripts leads to an prototype based result. So even if you use a private variable it is shared between instances. You can do this:

<pre><code>EventEmitter = -&gt;
 privateName = ""

 setName: (name) -&gt; privateName = name
 getName: -&gt; privateName
</code></pre>

.. leads to

<pre><code>emitter1 = new EventEmitter()
emitter1.setName 'Name1'

emitter2 = new EventEmitter()
emitter2.setName 'Name2'

console.log emitter1.getName() # 'Name1'
console.log emitter2.getName() # 'Name2'
</code></pre>

But be careful to put the private members before the public functions, because coffee script returns the public functions as object. Look at the compiled Javascript:

<pre><code>EventEmitter = function() {
 var privateName = "";

 return {
 setName: function(name) {
 return privateName = name;
 },
 getName: function() {
 return privateName;
 }
 };
};
</code></pre>

Does somebody know how to make private, non-static members in CoffeeScript? Currently I'm doing this, which just uses a public variable starting with an underscore to clarify that it shouldn't be used outside of the class:

<pre><code>class Thing extends EventEmitter
 constructor: (@_name) -&gt;

 getName: -&gt; @_name
</code></pre>

Putting the variable in the class makes it a static member, but how can I make it non-static? Is it even possible without getting "fancy"?

Private members in CoffeeScript?

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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有人知道如何在CoffeeScript中创建私有的、非静态的成员吗？目前我正在这样做，它只是使用了一个以下划线开头的公共变量，以澄清它不应该在类的外部使用：class Thing extends EventEmitter  constructor: (@_name) ->  getName: -> @_name将变量放...

问CoffeeScript中的私有成员？
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