Thanks! I'll try your version suggestion. I also understand why I
couldn't catch the error now too from this
post: https://groups.google.com/forum/#!topic/elm-discuss/vk4w_Ei8A84
Thanks,
Kevin
(Also, sorry for double posting!)
On Saturday, October 15, 2016 at 5:19:01 PM UTC-4, Peter Damoc wrote:
>
> You can check for a version of the storage schema and patch the data
> before sending it to Elm (or just drop it). In your case, you could also
> work with the fact that you know that the new version has comments:
>
> <script>
> const storedState = localStorage.getItem('model');
> var startingState = storedState ? JSON.parse(storedState) : null;
> if (! "comment" in startingState) {
> startingState = null;
> }
> try {
> elmApp = Elm.Main.fullscreen(startingState);
> }
> catch (e) {
> throw "it caught!";
> }
> elmApp.ports.setStorage.subscribe(function (state) {
> localStorage.setItem('model', JSON.stringify(state));
> })
> </script>
>
>
> Alternatively, you could pass the data as Value in your program and use
> multiple decoders to extract the data but that would be a little bit more
> complicated.
>
>
>
> On Thu, Oct 13, 2016 at 10:31 PM, Kevin Berridge <[email protected]
> <javascript:>> wrote:
>
>> Is there a way to catch the "You are trying to initialize module `Main`
>> with an unexpected argument." error when calling Elm.Main.fullscreen({})
>> with out of date arguments? I tried wrapping it in a try/catch, but the
>> catch is not running.
>>
>> What I'm really trying to do is pass in state that was persisted in local
>> storage as described here
>> https://medium.com/wunder-nerds/storing-and-restoring-the-state-in-elm-0-17-94874429dc1d#.gmkt7hrwu.
>>
>> But I changed my model, so now it errors. I'm happy to just forget the
>> state and start over when that happens, so if I could catch the error in JS
>> I could do that.
>>
>> Here's the JS I'm using. The throw in that catch block doesn't run.
>> <script>
>> const storedState = localStorage.getItem('model');
>> const startingState = storedState ? JSON.parse(storedState) :
>> null;
>> try {
>> elmApp = Elm.Main.fullscreen(startingState);
>> }
>> catch (e) {
>> throw "it caught!";
>> }
>> elmApp.ports.setStorage.subscribe(function (state) {
>> localStorage.setItem('model', JSON.stringify(state));
>> })
>> </script>
>>
>> And the JS error that is being thrown (but not being caught) is:
>> Uncaught Error: You are trying to initialize module `Main` with an
>> unexpected argument.
>> When trying to convert it to a usable Elm value, I run into this problem:
>>
>> I ran into the following problems:
>>
>> Expecting null but instead got: {...}
>> Expecting an object with a field named `comment` at _.distractions[4] but
>> instead got: {...}
>>
>> I truncated the object properties in that message. That error is
>> correct, 'comment' was added to my elm model and therefore does not exist
>> in the previously stored state that it is trying to deserialize.
>>
>> Thanks in advance,
>> Kevin
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "Elm Discuss" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to [email protected] <javascript:>.
>> For more options, visit https://groups.google.com/d/optout.
>>
>
>
>
> --
> There is NO FATE, we are the creators.
> blog: http://damoc.ro/
>
--
You received this message because you are subscribed to the Google Groups "Elm
Discuss" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
