Hi Jimmy - Thanks very much for that! I'll try that - it sounds good to me! Bye for now - - Andy Jimmy Wylie wrote:
Hi Andy,
If I remember right, runhaskell is expecting a full fledged haskell program with a "main" defined. Instead, you've sent it a module, which it isn't expecting, so you're getting a parse error on the "where". If you remove the "Module parseCSV where" from the top of your file, and try again, you'll get a "not in scope 'main' " error.
So you can test this a couple of ways. An easy way would be to open a terminal window and type "ghci", to open up ghc's Interpreter. Then, at the prompt type:
:l parseCSV.hs (or whatever the name of your file is)
Now, ghci, has loaded up all the functions defined in your file. So now, you can invoke your functions:
*Main> parseCSV "a,b,c,d\n" Right [["a","b","c","d"]]
If you're really adamant about using runhaskell, what you need to do is define a main function that opens up a file, use hGetContents to read the file as a String, and then invoke parseCSV on that String.
In order to take command line arguments, you'll want this: http://haskell.org/ghc/docs/6.12.1/html/libraries/base-4.2.0.0/System-Enviro...
Good Luck, Jimmy
On 10/16/10 12:23 AM, Andy Elvey wrote:
Hi all -
I'm just trying to get the simple csv file parser from "Real World Haskell" working. However, I've got a problem. Here's the code -
-- A simple csv parser Module parseCSV where import Text.ParserCombinators.Parsec
csvFile = endBy line eol line = sepBy cell (char ',') cell = many (noneOf ",\n") eol = char '\n'
parseCSV :: String -> Either ParseError [[String]] parseCSV input = parse csvFile "(unknown)" input
( Btw, I'm running Ubuntu 10.04, GHC 6.12.1 )
When I try to run this (using "runhaskell parseCSV.hs test.csv" ) I get the error - parseCSV.hs:4:16: parse error on input `where'
This has me really puzzled - as far as I can see, the first line looks identical to a number of similar programs that I've found (while searching for a solution to this). So, if anyone can let me know what is causing this, that'd be great! Many thanks in advance - - Andy
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