localStorage support.

[hemanth]

@thejameskyle First cut. Let me know if this approach is OK with you. WRT #71

[sebmck]

A check for the existence of localStorage would be good to support browsers that don't have it.

[hemanth]

@sebmck Was wondering the same, looks like only Opera mini doesn't have it, yet!

[hemanth]

@sebmck Added a MayBe construct, what say ;) ?

[sebmck]

@hemanth Bit overkill. I was suggesting more if (window.localStorage) localStorage.setItem("foo", "bar");. Your solution wont work either because the localStorage reference will throw a ReferenceError because it's not declared.

[hemanth]

@sebmck Duh! yeah, I was overwhelmed by mayBe, heh heh, reverting it to a simpler version.

[hemanth]

@sebmck Done 🐱

[jamiebuilds]

@hemanth Could you actually clean up these commits by rebasing your commit onto the latest master?

[sparty02]

@hemanth I've found this wiki to be useful in respect to rebasing pull requests , and squashing if need be

[hemanth]

@sparty02 Thanks, i'm aware of it, I fetched and merged your branch, hence the older commits have appeared.

[hemanth]

@thejameskyle Done.

[sparty02]

@hemanth You may want to move the local storage call up above where options are set on the repl instance:

this.options = _.assign(new Options(), state);

(so that options can be persisted too).

[hemanth]

👍

@sparty02 Done :)

[sparty02]

Local storage is an interesting idea, but I wonder if it would be confusing at all if a user came back to the site and there was all of a sudden input (via local storage) in their REPL. I definitely think persisting options is nice, I'm just concerned about how to effectively persist the code.

I'm almost wondering if this should be beefed up into some kind of "save session for later" feature (which could key into local storage by ID). This could then be pulled up via a menu.

Note, if it was taken this far, this could tie into #59 (via how to seed the REPL input from a dropdown) and #66 (the idea of 'saving' a session for later in a more robust way)

Just some thoughts......

[hemanth]

@sparty02 I would vote to get this rolling first and improvise later?

I have come across few online REPLs that save the previous code as is and is not confusing, maybe we must roll and wait for feedback from users?

[gaearon]

Note localStorage.setItem and localStorage.getItem throw on iOS in Private Mode.
Not that it's very important to support REPL on iOS, but not nice to crash either.

[jamiebuilds]

Note localStorage.setItem and localStorage.getItem throw on iOS in Private Mode.
Not that it's very important to support REPL on iOS, but not nice to crash either.

It's probably fine to just wrap these in try-catch blocks. @hemanth mind doing that?

[gaearon]

It's probably fine to just wrap these in try-catch blocks.

This is what I usually do, yeah.

[hemanth]

@thejameskyle No other options left, I had created a MayBe monad :D which was an overkill :)

[jamiebuilds]

I would just leave it as a try-catch

try {
  state = JSON.parse(localStorage.getItem('replState'));
} catch(e) {}

[hemanth]

@thejameskyle Done.

[hemanth]

@thejameskyle @sebmck 🐱

[jamiebuilds]

Thanks!

[hemanth]

Thank you!