[Haskell-cafe] Tracing Prelude.read exceptions
dokondr at gmail.com
Sun Dec 11 19:19:01 CET 2011
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?
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Haskell-Cafe