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Carl Dawkins
Web Development Techdegree Student 5,190 Pointsplanets.map(planet => createPlanetHTML(planet)).join('');
I get that planets.map makes a new array, that contains the result of passing both objects properties through the following function
createPlanetHtml()
But...
planets.map(planet => createPlanetHTML(planet)).join('');
// ^ planet ^ planet again
What is happening with the planet parameter in this instance and what is being passed to it for this to work?
1 Answer
Allan Cheow (he/him)
Full Stack JavaScript Techdegree Student 12,808 PointsHi Carl Dawkins,
In the example you provided
planets.map(planet => createPlanetHTML(planet)).join('');
// ^ planet ^ planet again
The "planet" in reference is the argument. Since we're using the arrow function, this variable can be named anything you like. To see a more traditional format, I believe you can interpret it like this:
planets.map(
function(planet) {
return createPlanetHTML(planet);
}
).join('');
It's a function within a function.
Hope this helps clarify things a little more.