Macrowski: Madsy, yeah, that’s better than mutating the array
Kimple: Well, how big is the array
Kimple: If you’re talking a multiple megabyte array you probably dont want to make a new one
Kimple: And would like to reuse the memory
Kimple: Also context is important. i’d say for most programs most of the time that filter is the right choice.
Bautiste: Does anyone know how to select an id of a div that is currenlty being shown then running a function based on the div being displayed
Budish: There’s something to be said for efficiency for larger arrays, yep. And there is something to be said for not having old “undefined” elements around.
Macrowski: Not sure what you are using that is leaving undefineds around.
Kimple: I’d avoid splice, since using that to filter in place will be On2
Marcone: Macrowski & tcsc : Thanks for the help. It’s not like there is some magic better way in other languages either. Unless you use linked lists or some other structure which isn’t random access
Kimple: You can do an in place filter in On. i’d recommend against it unless you have high performance requirements huge arrays or a 60fps limit
Kimple: You can remove in O1 from arrays
Hargenrader: Splice is the most powerful array method since you can add and remove indexes anywhere in the array, but readjusting indexes for all following indexes is very slow
Kimple: ArridxToRemove = arrarr.length-1; arr.pop
Demott: Use splice only when you need that extra power and be very cautious when using it in loops
Macrowski: Tcsc, but that wouldn’t maintain the order
Kimple: But how often do you care?
Kimple: Maybe 25% of the time?
Neglia: Tcsc: O1 if you don’t count the time complexity of arr.pop :-
Kimple: You can also do arr.length = arr.length-1;
Macrowski: Tcsc, I’d say quite often
Kimple: Idk if i can remember the last time that i needed to maintain the order when it wasn’t a sorted list or something
Kimple: You can filter in place in On and maintain order though
Dacamara: Tcsc: But nice trick, I didn’t think of using pop
Vanhamme: My immediate need didn’t need to preserve order
Kimple: It literally just does filter but you write to the earlier part of the array you’re in.
Boiles: Why are Promises useful?
Macrowski: Annoymouse, for handling async code
Iino: Macrowski: hey! Long time no see
Delerme: Macrowski: what’s wrong with callbacks?
Macrowski: Annoymouse, you can avoid callback hell more easily
Macrowski: Nothing wrong with callbacks, promises is just an abstraction, there are still callbacks, but not nested
Mantilia: But in all the contexts that I’ve seen them used they seem to do the same thing as callbacks
Tietjen: I used it recently to do two xmlhttprequests at the same time and have it call me back when both are done, it’s great for that
Macrowski: Annoymouse, right, they do pretty much the same thing, but the flow is more linear, instead of having to read nested callabacks
Sponseller: Alex: i guess that’s better than nesting them
Ashcroft: Macrowski: it seems like there are many implementations
Dykema: Is there any standard or popular one I should use
Macrowski: Annoymouse, there is a spec, so they should all behave the same
Macrowski: Annoymouse, they come built-in with ES6
Macrowski: They are in browsers, and io.js already
Adee: Macrowski: is it safe to ***ume ES6 support already?
Macrowski: Annoymouse, Promises is just a library, so yes, just include polyfill