On Fri, Dec 14, 2018 at 11:22:38AM +0000, Tom Ellis wrote:
On Fri, Dec 14, 2018 at 11:49:45AM +0100, Damien Mattei wrote:
another question with Haskell, again with my database but that is again related to Monads:
Damien, it's very hard to read your posts because they consist of snippets of code interspersed with commentary. You'll probably get much better responses if you post single, very small, well-formatted examples of sample code.
Anyway, the ultimate answer to your query is "use do-notation". Your getBS_WDS would be clearer written something like:
And ultimately I think you wanted to do something with lg and tst: ``` getBD_WDS :: Connection -> String -> IO Float getBD_WDS conn name = do let qry_head = "select DNUM from WDS where DISC = ?" :: Query bd_rows <- query conn qry_head (Only name) let lg = Prelude.length bd_rows putStrLn (if lg > 1 then "some" else "one or zero") let noBDtxt :: Text noBDtxt = fromOnly (Prelude.head bd_rows) noBDstr :: String noBDstr = Text.unpack noBDtxt noBDfp :: Float noBDfp = read noBDstr return noBDfp ```