XMLHttpRequest `response` property doesn't exist in IE9

[toretore]

The response property as used here:

https://github.com/elm-lang/http/blob/master/src/Native/Http.js#L154

was only added to IE10 according to https://msdn.microsoft.com/en-us/library/hh872881(v=vs.85).aspx

This results in a "Given an invalid JSON" error, or "This is not valid JSON!" in master at

https://github.com/elm-lang/core/blob/master/src/Elm/Kernel/Json.js#L149

as string will be undefined.

I'm not sure about the correct solution, especially with streaming or large payloads, but I've confirmed that in my simple case of a small JSON response, manually changing the generated JS to use responseText makes it work in IE9.

Edit: I should add that this is tested in IE11 in IE9 "document mode".

[process-bot]

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[harmboschloo]

I'm having the same issue. Just as a reference, this is how superagent handles response and responseText here and here.