Can someone help me out here?

[boris-alexander]

Hi a few questions from a complete beginner

1. Where am I supposed to find the documentation for all of these functions? Am I supposed to read the documentation or is there a part of the class i am missing?
2. how does this work

list = list.filter(function (file) {
  return path.extname(file) === '.' + filterStr
})

Can someone give me a line by line explanation for this. what is it returning the t/f statement to? then the call back is something like callback(null, true/false)? That cant be. Im lost with this one. Too many functions that I dont know how to find, and too little explanation of what this is even doing.

Worth noting I have been able to make it this far no problem

[peppermints]

hi~here are some suggestions for you: @boris-alexander
If you are a beginner，I hope you learn a little bit of JavaScript's basic knowledge. And for this reason，you can‘t understand this code. Actually, this functions is very basic knowledge. As for what you say (find the documentation for all of these functions), I recommend you a mac app， Dash， it's what you want.