Arrow functions (also known as fat arrow functions) have a shorter syntax compared to traditional function expressions and lexically bind the this value. Arrow functions are also always anonymous.
Here we are using the shortest form, where the body is a simple expression and we can drop the parenthesis around the parameter since there is only one:
var numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
// Same as function(number) { return number * 2 }
var doubled = numbers.map(number => number * 2);
If we want multiple parameters, we can add the parenthesis and curly braces back:
// Same as function(runningTotal, number) { return runningTotal + number }
var sum = numbers.reduce((runningTotal, number) => runningTotal + number, 0);
Finally, more complex multistatement arrow functions can use curly braces:
// Here all we're really saving is the function() heading.
numbers.map(number =>
{
if (number % 3 == 0 && number % 5 === 0)
return "Fizz Buzz";
if (number % 3 === 0)
return "Fizz";
if (number % 5 === 0)
return "Buzz";
return number;
}).join("<br/>")
Arrow functions can also make your code less complex since they'll use the "this" of the surrounding scope, instead of introducing their own. This means you can avoid having to bind in many cases:
var cart =
{
items: [],
addItem: function(anItem)
{
console.log("Added " + anItem + "!");
this.items.push(anItem);
},
addAll: function(newItems)
{
// Before we'd have to do (function(anItem) { this.addItem(anItem) }).bind(this)
newItems.forEach(anItem => this.addItem(anItem));
}
}
cart.addAll(["pickels", "tomatoes", "cheese"])
To learn more about arrow functions, check out https://hacks.mozilla.org/2015/06/es6-in-depth-arrow-functions/
Some of these examples and explanations originally taken and modified from:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions
https://github.com/lukehoban/es6features#arrows
https://en.wikipedia.org/wiki/Fizz_buzz
60 comments
- posted 7 years ago by5m7ujgy567
- posted 6 years ago byMuito bom
- posted 5 years ago by123
- posted 5 years ago byAwesome. content
- posted 4 years ago byNice!
- posted 4 years ago byanItem
- posted 2 years ago byPakages
- posted 2 years ago byKjj
- posted a month ago byGithub.com
- posted a month ago by1
- posted a month ago by1
- posted a month ago by-1 OR 2+556-556-1=0+0+0+1 --
- posted a month ago by-1 OR 2+765-765-1=0+0+0+1
- posted a month ago by-1' OR 2+614-614-1=0+0+0+1 --
- posted a month ago by-1' OR 2+527-527-1=0+0+0+1 or 'Mr3Kb96k'='
- posted a month ago by-1" OR 2+891-891-1=0+0+0+1 --
- posted a month ago byif(now()=sysdate(),sleep(15),0)
- posted a month ago by0'XOR(if(now()=sysdate(),sleep(15),0))XOR'Z
- posted a month ago by0"XOR(if(now()=sysdate(),sleep(15),0))XOR"Z
- posted a month ago by(select(0)from(select(sleep(15)))v)/*'+(select(0)from(select(sleep(15)))v)+'"+(select(0)from(select(sleep(15)))v)+"*/
- posted a month ago by-1; waitfor delay '0:0:15' --
- posted a month ago by-1); waitfor delay '0:0:15' --
- posted a month ago by1 waitfor delay '0:0:15' --
- posted a month ago byX7DUvldV'; waitfor delay '0:0:15' --
- posted a month ago by-5 OR 509=(SELECT 509 FROM PG_SLEEP(15))--
- posted a month ago by-5) OR 439=(SELECT 439 FROM PG_SLEEP(15))--
- posted a month ago by-1)) OR 467=(SELECT 467 FROM PG_SLEEP(15))--
- posted a month ago byjWX2b0Wb' OR 913=(SELECT 913 FROM PG_SLEEP(15))--
- posted a month ago bynifm1y1w') OR 96=(SELECT 96 FROM PG_SLEEP(15))--
- posted a month ago bylxNTaB3L')) OR 906=(SELECT 906 FROM PG_SLEEP(15))--
- posted a month ago by1*DBMS_PIPE.RECEIVE_MESSAGE(CHR(99)||CHR(99)||CHR(99),15)
- posted a month ago by1'||DBMS_PIPE.RECEIVE_MESSAGE(CHR(98)||CHR(98)||CHR(98),15)||'
- posted a month ago by1'"
- posted a month ago by@@JnPxd
- posted a month ago by1
- posted a month ago by1
- posted a month ago by-1 OR 2+482-482-1=0+0+0+1 --
- posted a month ago by-1 OR 2+46-46-1=0+0+0+1
- posted a month ago by-1' OR 2+718-718-1=0+0+0+1 --
- posted a month ago by-1' OR 2+302-302-1=0+0+0+1 or 'hLC1X0AN'='
- posted a month ago by-1" OR 2+875-875-1=0+0+0+1 --
- posted a month ago by1*if(now()=sysdate(),sleep(15),0)
- posted a month ago by10'XOR(1*if(now()=sysdate(),sleep(15),0))XOR'Z
- posted a month ago by10"XOR(1*if(now()=sysdate(),sleep(15),0))XOR"Z
- posted a month ago by(select(0)from(select(sleep(15)))v)/*'+(select(0)from(select(sleep(15)))v)+'"+(select(0)from(select(sleep(15)))v)+"*/
- posted a month ago by1-1; waitfor delay '0:0:15' --
- posted a month ago by1-1); waitfor delay '0:0:15' --
- posted a month ago by1-1 waitfor delay '0:0:15' --
- posted a month ago by1eHJPjFNe'; waitfor delay '0:0:15' --
- posted a month ago by1-1 OR 202=(SELECT 202 FROM PG_SLEEP(15))--
- posted a month ago by1-1) OR 96=(SELECT 96 FROM PG_SLEEP(15))--
- posted a month ago by1-1)) OR 683=(SELECT 683 FROM PG_SLEEP(15))--
- posted a month ago by1WqTpbcT0' OR 157=(SELECT 157 FROM PG_SLEEP(15))--
- posted a month ago by1QOE8LUvh') OR 233=(SELECT 233 FROM PG_SLEEP(15))--
- posted a month ago by1gRsXSsZ1')) OR 164=(SELECT 164 FROM PG_SLEEP(15))--
- posted a month ago by1*DBMS_PIPE.RECEIVE_MESSAGE(CHR(99)||CHR(99)||CHR(99),15)
- posted a month ago by1'||DBMS_PIPE.RECEIVE_MESSAGE(CHR(98)||CHR(98)||CHR(98),15)||'
- posted a month ago by'"
- posted a month ago by����%2527%2522\'\"
- posted a month ago by@@gTZNV
sign in to comment