[Haskell-cafe] Tracing Prelude.read exceptions

[dokondr]

Hi,
I got quite used to a sequence providing simple data persistence :
1) Store my data to a file:
writeFile fileName (show someData)

2) Some time later read this data back:
line <- readFile fileName
let someData = read line :: SomeDataType

Having this done hundreds of times I now got stuck with step 2)  trying to
read moderately complex structure back. I get read exception in run-time:
fromList *** Exception: Prelude.read: no parse

I have checked and rechecked my types, data files, etc. - and still no idea.

So my question:
Is there any way to trace Prelude.read exceptions to see exactly on what
data element read fails in run-time?

Thanks!
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