con colMeta = fn t_formT :: (Type * Type) => { Nam : string, Show : t_formT.1 -> xbody, Widget : nm :: Name -> xml form [] [nm = t_formT.2], WidgetPopulated : nm :: Name -> t_formT.1 -> xml form [] [nm = t_formT.2], Parse : t_formT.2 -> t_formT.1, Inject : sql_injectable t_formT.1 } con colsMeta = fn cols :: {(Type * Type)} => $(Top.mapT2T colMeta cols) fun default (t ::: Type) (sh : show t) (rd : read t) (inj : sql_injectable t) name : colMeta (t, string) = {Nam = name, Show = txt, Widget = fn nm :: Name => <xml><textbox{nm}/></xml>, WidgetPopulated = fn (nm :: Name) n => <xml><textbox{nm} value={show n}/></xml>, Parse = readError, Inject = _} val int = default val float = default val string = default fun bool name = {Nam = name, Show = txt, Widget = fn nm :: Name => <xml><checkbox{nm}/></xml>, WidgetPopulated = fn (nm :: Name) b => <xml><checkbox{nm} checked={b}/></xml>, Parse = fn x => x, Inject = _} functor Make(M : sig con cols :: {(Type * Type)} constraint [Id] ~ cols table tab : ([Id = int] ++ mapT2T fstTT cols) val title : string val cols : colsMeta cols end) = struct open constraints M val tab = M.tab sequence seq fun create (inputs : $(mapT2T sndTT M.cols)) = id <- nextval seq; () <- dml (insert tab (foldT2R2 [sndTT] [colMeta] [fn cols => $(mapT2T (fn t :: (Type * Type) => sql_exp [] [] [] t.1) cols)] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] => fn input col acc => acc with nm = @sql_inject col.Inject (col.Parse input)) {} [M.cols] inputs M.cols with #Id = (SQL {id}))); return <xml><body> Inserted with ID {[id]}. </body></xml> fun save (id : int) (inputs : $(mapT2T sndTT M.cols)) = () <- dml (update [mapT2T fstTT M.cols] (foldT2R2 [sndTT] [colMeta] [fn cols => $(mapT2T (fn t :: (Type * Type) => sql_exp [T = [Id = int] ++ mapT2T fstTT M.cols] [] [] t.1) cols)] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] => fn input col acc => acc with nm = @sql_inject col.Inject (col.Parse input)) {} [M.cols] inputs M.cols) tab (WHERE T.Id = {id})); return <xml><body> Saved! </body></xml> fun update (id : int) = fso <- oneOrNoRows (SELECT tab.{{mapT2T fstTT M.cols}} FROM tab WHERE tab.Id = {id}); case fso : (Basis.option {Tab : $(mapT2T fstTT M.cols)}) of None => return <xml><body>Not found!</body></xml> | Some fs => return <xml><body><form> {foldT2R2 [fstTT] [colMeta] [fn cols :: {(Type * Type)} => xml form [] (mapT2T sndTT cols)] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] (v : t.1) (col : colMeta t) (acc : xml form [] (mapT2T sndTT rest)) => <xml> <li> {cdata col.Nam}: {col.WidgetPopulated [nm] v}</li> {useMore acc} </xml>) <xml/> [M.cols] fs.Tab M.cols} <submit action={save id}/> </form></body></xml> fun delete (id : int) = () <- dml (DELETE FROM tab WHERE Id = {id}); return <xml><body> The deed is done. </body></xml> fun confirm (id : int) = return <xml><body> <p>Are you sure you want to delete ID #{[id]}?</p> <p><a link={delete id}>I was born sure!</a></p> </body></xml> fun main () = rows <- queryX (SELECT * FROM tab AS T) (fn (fs : {T : $([Id = int] ++ mapT2T fstTT M.cols)}) => <xml> <tr> <td>{[fs.T.Id]}</td> {foldT2RX2 [fstTT] [colMeta] [tr] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] v col => <xml> <td>{col.Show v}</td> </xml>) [M.cols] (fs.T -- #Id) M.cols} <td> <a link={update fs.T.Id}>[Update]</a> <a link={confirm fs.T.Id}>[Delete]</a> </td> </tr> </xml>); return <xml><head> <title>{cdata M.title}</title> </head><body> <h1>{cdata M.title}</h1> <table border={1}> <tr> <th>ID</th> {foldT2RX [colMeta] [tr] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] col => <xml> <th>{cdata col.Nam}</th> </xml>) [M.cols] M.cols} </tr> {rows} </table> <br/> <form> {foldT2R [colMeta] [fn cols :: {(Type * Type)} => xml form [] (mapT2T sndTT cols)] (fn (nm :: Name) (t :: (Type * Type)) (rest :: {(Type * Type)}) [[nm] ~ rest] (col : colMeta t) (acc : xml form [] (mapT2T sndTT rest)) => <xml> <li> {cdata col.Nam}: {col.Widget [nm]}</li> {useMore acc} </xml>) <xml/> [M.cols] M.cols} <submit action={create}/> </form> </body></xml> end