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JavaScript JavaScript Functions Arrow Functions Create an Arrow Function

Posted by Blessed Marufu
Blessed Marufu
3,927 Points

arrow function

would kindly assist me to understand this

script.js 
const  greet = 'cool coders'  => { `Hi,cool coders !`};
connor ingold
connor ingold
5,382 Points
connor ingold
connor ingold
5,382 Points

Here an example of a working arrow function:

const greet = (someMsg) => { console.log(`the message: ${someMsg}`) }
greet("Hello world")

However, one thing to be aware of with arrow functions is that if they only have 1 parameter (like the example above) they don't need parentheses. So you can also do this:

const greet = someMsg => { console.log(`the message: ${someMsg}`) }
greet("Hello world")

And it's still completely fine.

2 Answers

Steven Parker
Steven Parker
229,786 Points
Steven Parker
Steven Parker
229,786 Points

The example shown isn't valid syntax. In particular:

const  greet = 'cool coders'  => { `Hi,cool coders !`};
               ^^^^^^^^^^^^^
               // this should be a parameter name, not a string in quotes

const  greet = 'cool coders'  => { `Hi,cool coders !`};
                                   ^^^^^^^^^^^^^^^^^^
                                   // this should be one or more complete code statements,
                                   // -or- don't use the brackets

const  greet = 'cool coders'  => { `Hi,cool coders !`};
                                       ^^^^^^^^^^^
                                       // you probably want an interpolation token here,
                                       // as was used in the original version of the function

So, for example, a function that takes a string argument and returns a greeting string that contains it could be defined this way:

const greet = val => `Hi, ${val}!`;

Also, as mentioned in the hint, since arrow functions are not "hoisted", you will need to define the function before the line that calls it.

Blessed Marufu
Blessed Marufu
3,927 Points
Blessed Marufu
Blessed Marufu
3,927 Points

thank you very much