Json.decode is not lazy

[Simon]

Been experimenting with the Json library.

I expected this to yield `[9, 9]` but instead it gave me an 'unexpected x found`. That's very surprising with the uncommented code as I use `succeed`. Likewise the `oneOf` line also gave that error. This wasn't what I expected, but perhaps I should have.  (Note that succeed was used when I decoded the commented json string with the `\"\"`.

microJson : String
microJson = "[{\"tag\": 123}, {\"tag\": 23x4}]"
-- microJson = "[{\"tag\": 123}, {\"tag\": \"\"}]"

dec1 : Decoder (List Int)
dec1 = list (succeed 9)
-- dec1 = list <| ("tag" := int)
-- dec1 = list (oneOf [ ("tag" := int), succeed 9 ])

[Janis Voigtländer]

Wouldn't a more appropriate description be the following?

"Json.decode only accepts input that is at least valid JSon."

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[Janis Voigtländer]

Maybe think about it this way: If you expected your example to work with 23x4, would you also expect it to work (by virtue of "laziness") with 23}4 or something similarly weird in that place?

[Simon]

Yes, apologies.

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[Joey Eremondi]

It's important to remember that Elm, unlike Haskell, is NOT a lazy language. If you want lazy behavior, you need to manually wrap things in functions (i.e. () -> a ), and call those functions when you want things to be evaluated.

Yes, apologies.

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