Json.Decode: Uncaught TypeError: Cannot read property 'tag' of undefined

[ivanceras]

This will occur when decoding json with recursive data structure type.

Uncaught TypeError: Cannot read property 'tag' of undefined

pointing to this line of code

function runHelp(decoder, value)
{
    switch (decoder.tag)

Here is a short gist for this issue

[jvoigtlaender]

This is a known issue, with known current workarounds. Check issue 873 at the elm-compiler repo.

[jvoigtlaender]

This is a known issue, with known current workarounds. Check issue 873 at the elm-compiler repo.