freeCodeCamp Challenge Guide: Everything Be True

Guide
23

Hello !

Here’s my straight to the point and easy to understand solution. I’m glad others reached the same solution, that means I’m doing something right :wink:

    function truthCheck(collection, pre) {
      // Is everyone being true?
      for (var i = 0; i < collection.length; i++) {
        if(!collection[i][pre]) return false;
      }
      return true;
    }
    //Flawless victory!
    truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex");
2 Likes
24

Hello @Venkateshwaran !

Well I’m no JS expert in here, but you solution is in principle like mine, and I think it can be described as follows:

In your for loop you have the if statement that checks on every object from the collection array that it has a property that’s truthy or falsy based on the second argument of the function, pre. All that is evaluated in a Boolean context and your condition was to check if the Boolean is false then return false, and given that the two states are mutually exclusive, to return true in the all other situations.
You can easily leave out the Boolean as is not really necessary and go for the direct and simplified form:

 if(!collection[i][pre]) return false;

From my point of view I understood what’s happening in there, and hope my explanation was correct & helpful. You can check my solution down 4 rows from yours :slight_smile:. It’s practically like yours.

Cheerio!

1 Like
25 
function truthCheck(collection, pre) {
  // Is everyone being true?
  flag = true;
  var x = collection.forEach(function(val){
    if(Boolean(val[pre])===false) flag = false;
  });
  return flag;
}

how about this?

28

A solution i found earlier:

  return collection.map(x => x[pre]).filter(Boolean).length === collection.length ? true : false;

what do you guys think? any feedback?

3 Likes