I found the error. I used "Renewable" as the name of the XML element tag when it should have been "Renewables" with a trailing s. Oops. Sorry for the spam -- Tim On Tue, Jul 31, 2012 at 10:55 AM, Tim Perry wrote:

Hi everyone,

I'm trying to learn to write XmlPicklers. I've been trying to follow the tutorial on the HaskelWiki, but it doesn't quite cover an issue I've run into.

http://www.haskell.org/haskellwiki/HXT/Conversion_of_Haskell_data_from/to_XM...

I have a ADTs like so:

data Plant = Plant

{ renewables :: [Renewable]

, rewewableMonthly :: [RenewableMonthly]

, waterHeating :: [WaterHeating]

, hvac :: [HVAC]

} deriving (Read, Show, Eq)

data Renewable = Renewable

{ dcRating :: Double -- kW

, annualTDV :: Double -- CA Energy Comm. TDV

} deriving (Read, Show, Eq)

data RenewableMonthly = RenewableMonthly

{ month :: Int

, cost :: Double

, demand :: Double

, energy :: Double

} deriving (Read, Show, Eq)

data WaterHeating = WaterHeating

{ whName :: String -- name for reference purposes.

, whQuantity :: Int ...

data HVAC = HVAC

{ slaStatus :: String -- Specific leakage area construction type.

, newCFM50 :: Double -- New building leakage in cubic feet per minute.

, existCFM50 :: Double

I want to use an XmlPickler to read and write this. The XML looks like this:

<Plant>

<Renewables DCRating="8.4" AnnualTDV="0" />

<RenewableMonthly Month="1" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="2" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="3" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="4" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="5" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="6" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="7" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="8" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="9" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="10" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="11" Cost="0" Demand="0" Energy="0" />

<RenewableMonthly Month="12" Cost="0" Demand="0" Energy="0" />

Running my code I get an error:

-- (1) readDocument: start processing document "1101_11-001 Walsh.xml" -- (1) getXmlContents: content read and decoded for "file:///fairoaks1/all_proj/1101%20PG&E%20CAHP%2011-12/CRM/EProDataExtractPlanning/XML%20samples/1101_11-001%20Walsh.xml" -- (1) getXmlContents' -- (1) readDocument: "1101_11-001 Walsh.xml" (mime type: "text/xml" ) will be processed -- (1) readDocument: "1101_11-001 Walsh.xml" processed

fatal error: document unpickling failed xpCheckEmptyContents: unprocessed XML content detected context: element "Plant" contents:

Is it possible to write an XmlPickler for this? Do I need to make Renewable, RenewableMonthly, WaterHeating, and HVAC all the same type with 4 constructors and use xpAlt? Ideas?

Thanks, Tim