Named Functions To The Rescue

Node
1

In the 'Named Functions To The Rescue Section" In “Asynchronous JavaScript” can anybody get the exercise to work?
When my code gets to the getRepositories() function, I get an error saying the callback is not a function and I cannot figure out why.

Thanks for any help.

2

I’ve found out that the problem emerges from the function names:

  • getCommits(repos) & getCommits(repos, callback)

  • getRepositories(user) & getRepositories(username, callback)

Due to their different params, they did not seem to cause the error. However, when I just tried to have a unique name for each function, it turned out to work fine. :smiley: (my node version is v14.15.4)

Below is the way I’ve adjusted the code:

console.log(‘Before’);

getUser(1, readRepositories);

console.log(‘After’);

function readRepositories(user) {
getRepositories(user.gitHubUsername, readCommits);
}

function readCommits(repos) {
getCommits(repos, displayReposCommits);
}

function displayReposCommits(commits) {
console.log(commits);
}

function getUser(id, callback) {
setTimeout(()=> {
console.log(‘Reading a user from a DB…’);
callback({id: id, gitHubUsername: ‘Gioia’});
}, 2000);

}

function getRepositories(username, callback) {
setTimeout(()=> {
console.log(‘Calling GitHub API…’);
console.log(callback);
callback({
username: username,
repositories: [‘repo1’, ‘repo2’, ‘repo3’]
});
}, 2000);

}

function getCommits(repos, callback) {
setTimeout(() => {
console.log(Reading commits ...);
console.log(callback);
callback({
repository: repos,
commits: [‘1st commit’, ‘2nd commit’]
});
}, 8000);
}

2 Likes
3

Ran into the same issue. Spent an hour troubleshooting. Thanks for sharing the solution. Renamed the callback functions like you did and everything works. Thank you!

4

I know this is an old post, but I recently ran into the same problem. I ended up renaming the functions as well. That’s great that I got it to work, but what happened here? Mosh said that you should be able to have functions with the same name as long as the parameters aren’t the same. I guess, maybe they changed this with a later version of node js or javascript?