Scope Training Days Project

I’ve worked through this project a couple times and can’t seem to get past this error…

/home/ccuser/workspace/learn-javascript_scope-training-days/trainingDays.js:38
return activities.join(’, ');
^

TypeError: Cannot read property ‘join’ of undefined
at getEventActivities (/home/ccuser/workspace/learn-javascript_scope-training-days/trainingDays.js:38:22)
at getEventMessage (/home/ccuser/workspace/learn-javascript_scope-training-days/trainingDays.js:56:84)
at Object. (/home/ccuser/workspace/learn-javascript_scope-training-days/trainingDays.js:59:1)
at Module._compile (module.js:571:32)
at Object.Module._extensions…js (module.js:580:10)
at Module.load (module.js:488:32)
at tryModuleLoad (module.js:447:12)
at Function.Module._load (module.js:439:3)
at Module.runMain (module.js:605:10)
at run (bootstrap_node.js:427:7)

Here’s my code…

const getAllEvents = () => {
return [‘Marathon’, ‘Triathlon’, ‘Decathlon’];
};

const getRandomEvent = () => {
const allEvents = getAllEvents();
const event = allEvents[Math.floor(Math.random() * allEvents.length)];
return event;
};

const getEventActivities = (event) => {
const allEvents = getAllEvents();

if (!allEvents.includes(event)) {
return null;
}

let activities;
if (event === ‘Marathon’) {
const activities = [‘Running’];
}
if (event === ‘Triathlon’) {
const activities = [‘Running’, ‘Cycling’, ‘Swimming’];
}
if (event === ‘Decathlon’) {
const activities = [‘Running’, ‘Hurdles’, ‘Javelin throw’, ‘Discus Throw’, ‘Shot put’, ‘High Jump’];
}
return activities.join(’, ');
};

const getDaysToTrain = (event) => {
const allEvents = getAllEvents();
if (!allEvents.includes(event)) {
return null;
}
const eventTrainingTimes = {‘Marathon’: 50, ‘Triathlon’: 100, ‘Decathlon’: 200 };
return eventTrainingTimes[event];
};

getRandomEvent();
const getEventMessage = () => {
const myEvent = getRandomEvent();

console.log('Your event is a ’ + myEvent + '. Your event activities consist of ’ + getEventActivities(myEvent) + ‘. You have ’ + getDaysToTrain(myEvent) + ’ days to train.’);
}

getEventMessage();

You’ve got an error message telling you activities refers to undefined, so next you’d look at where you last assigned activities

Ah, activities was still defined as const. got it, thanks!

No, that’d get you something saying:
TypeError: Assignment to constant variable.
Or rather, it would if you tried to redefine it, which is not what you’re doing. That’s what const prevents.

What you’re doing is:

x = undefined;
x.join;

TypeError: Cannot read property 'join' of undefined

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