I have a data type in Haskell, which I want to convert into a list of tuples.
My structure:
data Projectdocs = Projectdocs {
docType :: String,
entityID :: String,
docURL :: String
}deriving Show
--A sample projectdocs type
Projectdocs{docType="txt",entityID="11012",docURL="www."}
--The output I want to create
["Projectdocs"]
[("doctype","txt"),("entityID","11012"),("docURL","www.")]
How can I do this?
Thanks,
If it's just for this one then you can easily hard-code it:
toTupleList :: Projectdocs -> [(String,String)]
toTupleList pd =
[ ("doctype" , docType pd)
, ("entityID", entityID pd)
, ("docURL" , docURL pd)
]
Note that your proposed initial element "Projectdocs"
doesn't have the type (String, String)
, so it cannot be a part of the list.
λ> toTupleList $ Projectdocs {docType="txt", entityID="11012", docURL="www."}
[("doctype","txt"),("entityID","11012"),("docURL","www.")]
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