Basically this Kata required us to create a polyfill filter method, if the client's browser doesn't support modern JavaScript

Thanks a lot! Got it!

Your solution has a bug and passes unexpected values into some of predicates. It's not a kata issue.

I have got a problem.
Do you know why?

mySolution:

for Test => passed

for Attempt => TypeError: "Cannot read properties of undefined"

Another knapsack kata? This is a duplicate of many existing knapsack katas.

confusing instructions...

I think the difficulty of this kata should be increased. 8kyu is for learning how to use filter, not implementing it. I barely even follow the solutions to this to be honest.

I don't think this should have been an 8kyu at all.

The description is very clear, just like Insisted has just said, it's probably you're not comfortable with Javascript's prototypes. In a word, when you don't know something, don't raise an issue: STFG.

The kata's description is enough if you know how to use Array.prototype.filter(). As stated in the description, You'd probably want to have a look at this. And also when you are stuck on any kata please use the Question tag and not the Issue one, as the purpose of those tags are expained here

the question and instructions weren't very clear.

really.

This one was cool for me, but I don't think it should be 8kyu.

One 8kyu kata is string concatenation and next one is prototyping, hmmmmm

I have used array.filter before. But I just started so would someone please explain this kata and the solution for those new to programming?
I would like to learn something from this but the solutions are not clear to me.

it's very confusing as for 8kyu