infinite type causes compiler hang

[auxsoft]

This bug was already posted in #1380, but that issue was closed in favor of #1231, which was also closed. The notes in this form instructs to visit #1240, but that issue is closed. So I'm posting this issue again. I should mention that I commented in those issues before posting this.

Compiling the following code crashes with out of memory error.

import Array exposing (Array)

fribble x y =
  Array.get y x
    |> Maybe.map (Array.set y x)
    |> Maybe.withDefault x

[process-bot]

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

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[xtian]

I'm having a similar issue when I try to use the API provided by dillonkearns/graphqelm in a certain way. My example is not as self-contained as I haven't dug into exactly what about the types is causing this issue, but I just thought I'd chime in to say this is affecting third-party packages as well.

Attempting to compile the following code in the Graphqelm Star Wars example on Ellie will hang/crash the compiler:

query =
    ["1004", "1001"]
        |> List.map (\id -> Query.human { id = Swapi.Scalar.Id id } human)
        |> List.foldl with (Query.selection identity)

EDIT: Now noticing that there are other issues on the tracker which may be more relevant to my issue. Not sure which one would be most correct though 🤷‍♂️

[MikaelMayer]

Workaround
I just had the same issue. To overcome that, I forced myself to annotate types to every top-level functions and also inner auxiliary functions, e.g.:

let aux a b c =

to

let aux: A -> B -> C -> D
    aux a b c =

It helped the compiler so much that there were no more out of memory issue trying to infer the type of a ill-written function (I found several bugs in my code afterwards)