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Comment by tomcam | Hacker News Reader

Sorry, it was the syntax up to the makeElement(`h1`); that I didn't understand:

  const h1 = () =>

Is this new syntax declaring a function named h1 that returns a function or what? I don't understand what the empty pair of parentheses means.

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Yes, this is a shortcut for:

    const h1 = function() {
      return makeElement('h1');
    }

Arrow functions without arguments need empty paranthesis.

They also have an implicit return if you don't use {}

To add to the other explanations: it's also important to point out that arrow functions are slightly different from regular functions in that they don't redefine `arguments` and `this` so these keywords behave like any other variable would in a closure.

So it's not just a syntactic shorthand but there's also a semantic difference.

Yes, it's ES6/ES2015. It's a lambda function ("fat arrow notation"). In the parentheses you would specify the arguments. An empty pair of parentheses means that the function does not expect any parameters.

OK, thanks. So it is the parameter list, not the return value

This is declaring a constant and assigning a function that takes no arguments to that constant.

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