[Haskell-beginners] Help with meaningful error message...
Sean Charles
sean at objitsu.com
Tue Jun 7 23:44:54 CEST 2011
OK, I am losing enough hair and accruing follicular damage more than I
can take tonight, what is wrong, what have I done that is stupid and
wrong etc...
called:
let routes = forwardRoutes M.empty csvdata -- [Record] from Text.CSV
implemented:
forwardRoutes m [] = m
forwardRoutes m (row:rows) =
case M.lookup m (row !! 0) of
Just route -> M.update m (row !! 1):route
Nothing -> M.insert from []
forwardRoutes m rows
error: scread.hs:101:2: parse error on input `forwardRoutes'
Um yeah, thanks, that's really helping me figure it out.
All I wanted to do was build a map of keys and values where each value
is a list that gradually accumulates(!) every row that ends at (!!1)
from the same location (!!0) of my spreadsheet. I started off zipping
with 'repeat []' and stuff but I just want to know what I have done to
annoy the compiler enough to want to taunt me with that message.
And, on the verge of posting I think the above code won't work anyway
because I am not passing the new Map from 'insert' through.......
ARGH!
:(
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