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JavaScript Basic Arrow Syntax

Posted by Lukas Bager
Lukas Bager
Courses Plus Student 361 Points

Would you recommend arrow syntax?

Would you recommend using arrow syntax, when using iterator methods such as .forEach() .map() and .filter() ?

Alexander La Bianca
Alexander La Bianca
15,959 Points

It is a preference thing, but I prefer the arrow syntax at it keeps the code cleaner. Especially when you have several .map() stacked it can keep your code more concise. and you are dealing with objects

//students -> array of student
//example student -> {name: 'alex', age:25, location: 'TX' }

const ages = students.map(student => student.age);
const names = students.map(student => student.name);
const locations = students.map(student => student.location);


//without arrow syntax
const ages = students.map(function(student) {
        return student.age;
});
.
.
.

2 Answers

Steven Parker
Steven Parker
229,783 Points
Steven Parker
Steven Parker
229,783 Points

It's important to be aware of the limitations of arrow functions: they do not have their own "this", "arguments", "super", or "new.target". And they cannot be used as constructors or generators.

But otherwise, I prefer them because they provide a more concise definition format, particularly for anonymous callback arguments.

For more information, see the MDN page on Arrow Functions.

Lukas Bager
PLUS
Lukas Bager
Courses Plus Student 361 Points
Lukas Bager
Lukas Bager
Courses Plus Student 361 Points

Thank you very much for the answers, it was very helpful :)