blocks|key|1967966|text|具有类似语法的Lambda函数包含在ECMAscript+6中，它们被称为“箭头函数”。举个例子：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1967967|["duck",+"cat",+"goat"].filter(el+=>+el.length+>+3);返回["duck",+"goat"]|style|CODE|1967968|目前在Firefox和Chrome的最新版本中都有支持。|1967969|要在针对较旧浏览器的JavaScript中使用此语法，有一些工具可以将ES6编译为更广泛支持的版本-例如，工具Babel或Traceur。|1967970|entityMap|0|LINK|mutability|MUTABLE|url|http://www.ecma-international.org/ecma-262/6.0/#sec-arrow-function-definitions|1|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions|2|https://www.chromestatus.com/feature/5047308127305728|3|https://babeljs.io/|4|https://github.com/google/traceur-compiler^0|I|C|0|0|0|1G|1I|G|0|3|7|1|B|6|2|0|1J|5|3|1P|7|4|0^^$0|@$1|2|3|4|5|6|7|11|8|@]|9|@$A|12|B|13|1|14]]|C|$]]|$1|D|3|E|5|6|7|15|8|@$A|16|B|17|F|G]|$A|18|B|19|F|G]]|9|@]|C|$]]|$1|H|3|I|5|6|7|1A|8|@]|9|@$A|1B|B|1C|1|1D]|$A|1E|B|1F|1|1G]]|C|$]]|$1|J|3|K|5|6|7|1H|8|@]|9|@$A|1I|B|1J|1|1K]|$A|1L|B|1M|1|1N]]|C|$]]|$1|L|3|-4|5|6|7|1O|8|@]|9|@]|C|$]]]|M|$N|$5|O|P|Q|C|$R|S]]|T|$5|O|P|Q|C|$R|U]]|V|$5|O|P|Q|C|$R|W]]|X|$5|O|P|Q|C|$R|Y]]|Z|$5|O|P|Q|C|$R|10]]]]

Lambda functions with similar syntax are included in <a href="http://www.ecma-international.org/ecma-262/6.0/#sec-arrow-function-definitions" rel="noreferrer">ECMAscript 6</a>, they're known as "arrow functions". An example:

<code>["duck", "cat", "goat"].filter(el =&gt; el.length &gt; 3);</code> returns <code>["duck", "goat"]</code>

There's currently support in recent versions of <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions" rel="noreferrer">Firefox</a> and <a href="https://www.chromestatus.com/feature/5047308127305728" rel="noreferrer">Chrome</a>. 

To use this syntax in JavaScript that's targeting older browsers there are tools that can compile ES 6 to a more widely supported version - for example the tools <a href="https://babeljs.io/" rel="noreferrer">Babel</a> or <a href="https://github.com/google/traceur-compiler" rel="noreferrer">Traceur</a>.

blocks|key|1754493|text|您可以使用typescript+(www.typescriptlang.org/)：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1754494|function+(d,+i)+{
++++return+"translate("+%2B+d.x+%2B+","+%2B+d.y+%2B+")";
}|code-block|syntax|javascript|1754495|会变成|1754496|(d,+i)+=>++"translate("+%2B+d.x+%2B+","+%2B+d.y+%2B+")"++|1754497|还有更多很酷的东西，比如输入：...如果你对此感兴趣的话|1754498|entityMap|0|LINK|mutability|MUTABLE|url|http://www.typescriptlang.org/^0|H|O|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|12|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|C|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

You could use typescript (<a href="http://www.typescriptlang.org" rel="noreferrer">www.typescriptlang.org/)</a>: 

<pre><code>function (d, i) {
 return "translate(" + d.x + "," + d.y + ")";
}
</code></pre>

would become

<pre><code>(d, i) =&gt; "translate(" + d.x + "," + d.y + ")" 
</code></pre>

and much more cool stuff, like typing: ... that's if you are into that

blocks|key|1967928|text|我开始为jQuery创建一个扩展器，它完全可以做你想要的事情。JS-Lambda|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1967929|例如在C#中：|1967930|++coll.TakeWhile(x+=>+x.index+<+3);|code-block|syntax|javascript|1967931|看起来像这样：|1967932|+$(coll).TakeWhile("x+=>+x.index+<+3");|1967933|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/Ruben-J/JS-Lambda^0|V|9|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|6|7|10|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|11|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|12|8|@]|9|@]|C|$]]|$1|M|3|N|5|H|7|13|8|@]|9|@]|C|$I|J]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

I started creating an extender for jQuery which does exactly the thing you are asking. 
<a href="https://github.com/Ruben-J/JS-Lambda" rel="noreferrer">JS-Lambda</a>

For example in C#:

<pre><code> coll.TakeWhile(x =&gt; x.index &lt; 3);
</code></pre>

Looks like:

<pre><code> $(coll).TakeWhile("x =&gt; x.index &lt; 3");
</code></pre>

blocks|key|1754596|text|Javascript有非常好的匿名函数，允许您创建您需要的lambdas+anyWhere作为函数，但其实现带有一些重复的单词和作用域创建：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1754597|function(name){
+++++return+"Hello,+"+%2B+name;
}|code-block|syntax|javascript|1754598|多亏了EcmaScript+2015，lambda+expresion现在可以用于javaScript，语法更简单，如Arrow+Function|offset|length|1754599|(name)+=>+"Hello,+"+%2B+name|1754600|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions^0|0|0|1N|E|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@$I|X|J|Y|1|Z]]|A|$]]|$1|K|3|L|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

Javascript has very nice anonymous functions that allows you to create lambdas anyWhere you need as a function but the implementation comes with some much words and scope creation repeating:

<pre><code>function(name){
 return "Hello, " + name;
}
</code></pre>

Thanks to EcmaScript 2015 lambda expresion is now available for javaScript with simpler syntax as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions" rel="nofollow">Arrow Function</a>

<pre><code>(name) =&gt; "Hello, " + name
</code></pre>

blocks|key|1968499|text|就是马修·麦克维！|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1968500|我也想做点贡献，看看这个例子|1968501|​|1968502|"use+strict";
/*+Lambda+Helper+to+print++*/
function+PrintLineForElement(element,+index,+array){
++document.write("a["+%2B+index+%2B+"]+=+"+%2B+JSON.stringify(element)%2B" ");
}
/*+function+to+print+array+*/
function+Print(a){
+++a.forEach(PrintLineForElement)
+++document.write(" ");
}
/*+user+model+*/
class+User{
		constructor(_id,_name,_age,_job){
			+this.id+=+_id;
+++++++this.name+=+_name;
			+this.age+=+_age;
+++++++this.job+=+_job;
		}
}+
/*+Provaider+users+*/
class+UserService{+

		constructor(){+}+
++++
		GetUsers(){
++++++++//fake+ajax+response
				let+data+=+[];	
++++++++data.push(new+User(1,"Juan",20,"AM"));
++++++++data.push(new+User(2,"Antonio",20,"AM"));
++++++++data.push(new+User(3,"Miguel+Angel",30,"Developer"));
++++++++data.push(new+User(4,"Bea",26,"AM"));
++++++++data.push(new+User(5,"David",24,"Developer"));+
++++++++data.push(new+User(6,"Angel",24,"Developer"));+
++++++++data.push(new+User(7,"David",34,"TeamLead"));
++++++++data.push(new+User(8,"Robert",35,"TeamLead"));
++++++++data.push(new+User(9,"Carlos",35,"TeamLead"));+++
				
++++++++return+data;
		}
}

const+userService+=+new+UserService();
const+users+=++userService.GetUsers();

//get+user+order+by+name
document.write("All+users+");
Print(users);

//get+user+order+by+name
document.write("Order+users+by+name+ASC+:+users.sort((a,b)=>{return+a.name+>+b.name+})");
Print(users.sort((a,b)=>{return+a.name+>+b.name;+}));
document.write("Order+users+by+name+DESC+:+users.sort((a,b)=>{return+a.name+<+b.name+})");
Print(users.sort((a,b)=>{return+a.name+<+b.name;+}));

//get+user+filter+by+age+
document.write("Only+users+oldest+or+equal+than+25+:+users.filter(+(w)+=>+{return+w.age+>=+25;}+)");
Print(users.filter(+(w)+=>+{return+w.age+>=+25;}+));+
document.write("Only+users+smallest+or+equal+than+25+:+users.filter(+(w)+=>+{return+w.age+<=+25;}+)");
Print(users.filter(+(w)+=>+{return+w.age+<=+25;}+));+

//GroupBY+
/**
*+custom+group+by+with+Array.prototype.keys
**/

Array.prototype.groupBy+=+function(f)
{
++let+groups+=+[];
++this.forEach(+function(+o+)
++{
++++let+group+=++f(o)+;
++++groups[group]+=+groups[group]+%7C%7C+[];
++++groups[group].push(+o+);++
++});

++return+Object.keys(groups).map(+function(+group+)
++{
++++return+groups[group];+
++})
}

document.write("Group+user+by+age+");
Print(users.groupBy(+(w)+=>+{return+w.age+}+));+

document.write("Group+user+by+job+");
Print(users.groupBy(+(w)+=>+{return+w.job+}+));+

document.write("Group+user+by+job");
Print(users.groupBy(+(g)+=>+{return+[g.job]+}+));

document.write("Group+user+by+job+and+age+then+order+by+name+");
Print(users.sort((a,b)=>{return+a.job+>+b.job}).groupBy(+(g)+=>+{return+[g.job%2Bg.age]+}+));

document.write("Group+user+by+job+and+age+then+order+by+name+and+filter+where+age+<+25+and+job+equal+AM+");
Print(users.sort((a,b)=>{return+a.job+>+b.job}).filter((w)=>{+return+w.age<25+%7C%7C+w.job+==+"AM"+}).groupBy(+(g)+=>+{return+[g.job%2Bg.age]+}+));|code-block|syntax|javascript|1968503|1968504|https://jsfiddle.net/angelfragap/0b5epjw3/29/|offset|length|1968505|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|0|0|0|19|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Y|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|Z|8|@]|9|@]|A|$I|J]]|$1|K|3|E|5|6|7|10|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|11|8|@]|9|@$N|12|O|13|1|14]]|A|$]]|$1|P|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|Q|$R|$5|S|T|U|A|$V|M]]]]

Exact Matthew Mcveigh!! 

I want to contribute too, see this example 

<div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>"use strict";
/* Lambda Helper to print */
function PrintLineForElement(element, index, array){
 document.write("a[" + index + "] = " + JSON.stringify(element)+"&lt;br&gt;");
}
/* function to print array */
function Print(a){
 a.forEach(PrintLineForElement)
 document.write("&lt;br&gt;");
}
/* user model */
class User{
		constructor(_id,_name,_age,_job){
			 this.id = _id;
 this.name = _name;
			 this.age = _age;
 this.job = _job;
		}
} 
/* Provaider users */
class UserService{ 

		constructor(){ } 
 
		GetUsers(){
 //fake ajax response
				let data = [];	
 data.push(new User(1,"Juan",20,"AM"));
 data.push(new User(2,"Antonio",20,"AM"));
 data.push(new User(3,"Miguel Angel",30,"Developer"));
 data.push(new User(4,"Bea",26,"AM"));
 data.push(new User(5,"David",24,"Developer")); 
 data.push(new User(6,"Angel",24,"Developer")); 
 data.push(new User(7,"David",34,"TeamLead"));
 data.push(new User(8,"Robert",35,"TeamLead"));
 data.push(new User(9,"Carlos",35,"TeamLead")); 
				
 return data;
		}
}

const userService = new UserService();
const users = userService.GetUsers();

//get user order by name
document.write("All users &lt;/br&gt;");
Print(users);

//get user order by name
document.write("Order users by name ASC : users.sort((a,b)=&gt;{return a.name &gt; b.name })&lt;/br&gt;");
Print(users.sort((a,b)=&gt;{return a.name &gt; b.name; }));
document.write("Order users by name DESC : users.sort((a,b)=&gt;{return a.name &lt; b.name })&lt;/br&gt;");
Print(users.sort((a,b)=&gt;{return a.name &lt; b.name; }));

//get user filter by age 
document.write("Only users oldest or equal than 25 : users.filter( (w) =&gt; {return w.age &gt;= 25;} )&lt;/br&gt;");
Print(users.filter( (w) =&gt; {return w.age &gt;= 25;} )); 
document.write("Only users smallest or equal than 25 : users.filter( (w) =&gt; {return w.age &lt;= 25;} )&lt;/br&gt;");
Print(users.filter( (w) =&gt; {return w.age &lt;= 25;} )); 

//GroupBY 
/**
* custom group by with Array.prototype.keys
**/

Array.prototype.groupBy = function(f)
{
 let groups = [];
 this.forEach( function( o )
 {
 let group = f(o) ;
 groups[group] = groups[group] || [];
 groups[group].push( o ); 
 });

 return Object.keys(groups).map( function( group )
 {
 return groups[group]; 
 })
}

document.write("Group user by age &lt;/br&gt;");
Print(users.groupBy( (w) =&gt; {return w.age } )); 

document.write("Group user by job &lt;/br&gt;");
Print(users.groupBy( (w) =&gt; {return w.job } )); 

document.write("Group user by job&lt;/br&gt;");
Print(users.groupBy( (g) =&gt; {return [g.job] } ));

document.write("Group user by job and age then order by name &lt;/br&gt;");
Print(users.sort((a,b)=&gt;{return a.job &gt; b.job}).groupBy( (g) =&gt; {return [g.job+g.age] } ));

document.write("Group user by job and age then order by name and filter where age &lt; 25 and job equal AM &lt;/br&gt;");
Print(users.sort((a,b)=&gt;{return a.job &gt; b.job}).filter((w)=&gt;{ return w.age&lt;25 || w.job == "AM" }).groupBy( (g) =&gt; {return [g.job+g.age] } ));</code></pre>
</div>
</div>


<a href="https://jsfiddle.net/angelfragap/0b5epjw3/29/" rel="nofollow noreferrer">https://jsfiddle.net/angelfragap/0b5epjw3/29/</a>

Is there a framework or post processor for JavaScript that supports lambda syntax like in C#?

Function definitions in CoffeeScript seem to look like lambdas but I have not looked into them thoroughly.

Can anyone tell me, can I use lambda syntax in JavaScript?

Is there a C#-like lambda syntax in JavaScript?

jQuery

JSON

有没有像C#那样支持lambda语法的JavaScript框架或后处理器？CoffeeScript中的函数定义看起来像lambda，但我还没有深入研究过它们。有人能告诉我，我能在JavaScript中使用lambda语法吗？

问在JavaScript中有类似C#的lambda语法吗？
EN

回答 5

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问在JavaScript中有类似C#的lambda语法吗？EN

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问在JavaScript中有类似C#的lambda语法吗？
EN