Core: 5.1.0 Ports variable 'result' not defined/in scope?

[keithasaurus]

Upgraded to 5.1.0, and now on any port send I'm getting the following error:
ReferenceError: Can't find variable: result

looks like there is no result variable in scope at the line var value = result._0; in the following compiled JS:

function setupIncomingPort(name, callback)
    {
        var sentBeforeInit = [];
        var subs = _elm_lang$core$Native_List.Nil;
        var converter = effectManagers[name].converter;
        var currentOnEffects = preInitOnEffects;
        var currentSend = preInitSend;

        // CREATE MANAGER

        var init = _elm_lang$core$Native_Scheduler.succeed(null);

        function preInitOnEffects(router, subList, state)
        {
            var postInitResult = postInitOnEffects(router, subList, state);

            for(var i = 0; i < sentBeforeInit.length; i++)
            {
                postInitSend(sentBeforeInit[i]);
            }

            sentBeforeInit = null; // to release objects held in queue
            currentSend = postInitSend;
            currentOnEffects = postInitOnEffects;
            return postInitResult;
        }

        function postInitOnEffects(router, subList, state)
        {
            subs = subList;
            return init;
        }

        function onEffects(router, subList, state)
        {
            return currentOnEffects(router, subList, state);
        }

        effectManagers[name].init = init;
        effectManagers[name].onEffects = F3(onEffects);

        // PUBLIC API

        function preInitSend(value)
        {
            sentBeforeInit.push(value);
        }

        function postInitSend(incomingValue)
        {
            var value = result._0;
            var temp = subs;
            while (temp.ctor !== '[]')
            {
                callback(temp._0(value));
                temp = temp._1;
            }
        }

[process-bot]

Thanks for the issue! Make sure it satisfies this checklist. My human colleagues will appreciate it!

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[littleStudent]

having the exact same issue.
popped up after upgrading to 5.1.0

[keithasaurus]

Further complicating this issue is that elm-package won't install [email protected] with the following version string in elm-package.json: "elm-lang/core": "5.0.0 <= v < 5.0.1",

Is there a workaround for installing a specific version?

[lukewestby]

working on a fix, will submit in 1 minute

[evancz]

@rtfeldman, I think this is from your change https://github.com/elm-lang/core/commit/5ec47ca969d3bc995678c8cff73132daf5eeb8b4

[evancz]

Thanks again to @keithasaurus for the report and @lukewestby for the very quick fix! Sorry to everyone who ran into this. A 5.1.1 is out with the fix, but please let me know if there are any further issues.