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--description--

Just like a regular function, you can pass arguments into an arrow function.

const doubler = (item) => item * 2;
doubler(4);

doubler(4) would return the value 8.

If an arrow function has a single parameter, the parentheses enclosing the parameter may be omitted.

const doubler = item => item * 2;

It is possible to pass more than one argument into an arrow function.

const multiplier = (item, multi) => item * multi;
multiplier(4, 2);

multiplier(4, 2) would return the value 8.

--instructions--

Rewrite the myConcat function which appends contents of arr2 to arr1 so that the function uses arrow function syntax.

--hints--

You should replace the var keyword.

assert.notMatch(code, /var/g);

myConcat should be a constant variable (by using const).

assert.match(code, /const\s+myConcat/g);

myConcat should be an arrow function with two parameters

assert(
/myConcat=\(\w+,\w+\)=>/.test(__helpers.removeJSComments(code).replace(/\s/g, '')) &&
typeof myConcat === 'function'
);

myConcat() should return [1, 2, 3, 4, 5].

assert.deepEqual(myConcat([1, 2], [3, 4, 5]), [1, 2, 3, 4, 5]);

The function keyword should not be used.

assert.notMatch(code, /function/g);

--seed--

--seed-contents--

var myConcat = function(arr1, arr2) {
return arr1.concat(arr2);
};

console.log(myConcat([1, 2], [3, 4, 5]));

--solutions--

const myConcat = (arr1, arr2) =>  {
return arr1.concat(arr2);
};

console.log(myConcat([1, 2], [3, 4, 5]));