node.js - What is the "=>" syntax in nodejs? -


this question has answer here:

i'm wondering difference between anonymous function:

callback = function (a) {return a}

and using "=>" notation? 

callback = (a) => {return a}

is more syntactic sugar?

() => called arrow function of javascript, introduced in ecma script 6. it's useful more intuitive handling of current object context.

reference link new features of ecma script 6.


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