Mini linter final word count difference

[cloud4671013107]

https://www.codecademy.com/paths/full-stack-engineer-career-path/tracks/fscp-javascript-syntax-part-ii/modules/fecp-learn-javascript-syntax-iterators/projects/mini-linter

const betterWords = storyWords.filter(function(x){
return !unnecessaryWords.includes(x)}) // THE FINAL WORD COUNT IS 182.

---

const betterWords = storyWords.filter(function(x){
if (x != unnecessaryWords[0] && x != unnecessaryWords[1] && x != unnecessaryWords[2])
return x}) // THE FINAL WORD COUNT IS 179.

---

Could anybody tell me why the word count is different when both of these filter functions should do exactly the same job? Many thanks

[mirja_t]

Hi,
they don’t do the same thing:

@cloud4671013107

return !unnecessaryWords.includes(x)

This is either true or false – a bolean. That is what the filter method expects as a return value from the callback function.

@cloud4671013107

return x

This returns the value stored in the filtered array. That is not what the filter function expects. I don’t know why the filter has 3 items less, but the first example is the better solution and probably stores the correct result.

[cloud4671013107]

Thank you for the response, I put both of the different paragraphs into a WordCounter online and they both have returned 178 words. I do not understand

[mirja_t]

Do you pass an array to the function as an argument or a string?

[cloud4671013107]

I believe as a string

[mirja_t]

Then that will be the problem. includes() can also search strings for a match, but that will be different than searching an array.
Example:

const arr = ['climb', 'hill'];
const str = 'climb hill';

console.log(arr.includes('hi')); // false
console.log(str.includes('hi')); // true

So if you pass a string and look for includes, it will find matches that are just a part of a word as well.

[cloud4671013107]

Ahhhh thank you so much!