con rawMeta = fn t :: Type => {New : transaction t, Inj : sql_injectable t} con colMeta' = fn (row :: {Type}) (t :: Type) => {Header : string, Project : $row -> transaction t, Update : $row -> t -> transaction ($row), Display : t -> xbody, Edit : t -> xbody, Validate : t -> signal bool} con colMeta = fn (row :: {Type}) (global_t :: (Type * Type)) => {Initialize : transaction global_t.1, Handlers : global_t.1 -> colMeta' row global_t.2} con aggregateMeta = fn (row :: {Type}) (acc :: Type) => {Initial : acc, Step : $row -> acc -> acc, Display : acc -> xbody} structure Direct = struct con metaBase = fn actual_input :: (Type * Type) => {Display : actual_input.2 -> xbody, Edit : actual_input.2 -> xbody, Initialize : actual_input.1 -> transaction actual_input.2, Parse : actual_input.2 -> signal (option actual_input.1)} datatype metaBoth actual input = NonNull of metaBase (actual, input) * metaBase (option actual, input) | Nullable of metaBase (actual, input) con meta = fn global_actual_input :: (Type * Type * Type) => {Initialize : transaction global_actual_input.1, Handlers : global_actual_input.1 -> metaBoth global_actual_input.2 global_actual_input.3} con editableState (ts :: (Type * Type * Type)) = (ts.1, ts.3) fun editable [ts] [rest] [nm :: Name] [[nm] ~ rest] name (m : meta ts) : colMeta ([nm = ts.2] ++ rest) (editableState ts) = let fun doMr mr = {Header = name, Project = fn r => mr.Initialize r.nm, Update = fn r s => vo <- current (mr.Parse s); return (case vo of None => r | Some v => r -- nm ++ {nm = v}), Display = mr.Display, Edit = mr.Edit, Validate = fn s => vo <- mr.Parse s; return (Option.isSome vo)} in {Initialize = m.Initialize, Handlers = fn data => case m.Handlers data of NonNull (mr, _) => doMr mr | Nullable mr => doMr mr} end con readOnlyState (ts :: (Type * Type * Type)) = (ts.1, ts.3) fun readOnly [ts] [rest] [nm :: Name] [[nm] ~ rest] name (m : meta ts) : colMeta ([nm = ts.2] ++ rest) (readOnlyState ts) = let fun doMr mr = {Header = name, Project = fn r => mr.Initialize r.nm, Update = fn r _ => return r, Display = mr.Display, Edit = mr.Display, Validate = fn _ => return True} in {Initialize = m.Initialize, Handlers = fn data => case m.Handlers data of NonNull (mr, _) => doMr mr | Nullable mr => doMr mr} end con metaBasic = fn actual_input :: (Type * Type) => {Display : actual_input.2 -> xbody, Edit : source actual_input.2 -> xbody, Initialize : actual_input.1 -> actual_input.2, InitializeNull : actual_input.2, IsNull : actual_input.2 -> bool, Parse : actual_input.2 -> option actual_input.1} con basicState = source fun basic [ts ::: (Type * Type)] (m : metaBasic ts) : meta (unit, ts.1, basicState ts.2) = {Initialize = return (), Handlers = fn () => NonNull ( {Display = fn s => , Edit = m.Edit, Initialize = fn v => source (m.Initialize v), Parse = fn s => v <- signal s; return (m.Parse v)}, {Display = fn s => , Edit = m.Edit, Initialize = fn v => source (case v of None => m.InitializeNull | Some v => m.Initialize v), Parse = fn s => v <- signal s; return (if m.IsNull v then Some None else case m.Parse v of None => None | Some v' => Some (Some v'))})} fun nullable [global] [actual] [input] (m : meta (global, actual, input)) = {Initialize = m.Initialize, Handlers = fn d => case m.Handlers d of Nullable _ => error Don't stack calls to Direct.nullable! | NonNull (_, ho) => Nullable ho} type intGlobal = unit type intInput = basicState string val int : meta (intGlobal, int, intInput) = basic {Display = fn s => {[s]}, Edit = fn s => , Initialize = fn n => show n, InitializeNull = "", IsNull = eq "", Parse = fn v => read v} type stringGlobal = unit type stringInput = basicState string val string : meta (stringGlobal, string, stringInput) = basic {Display = fn s => {[s]}, Edit = fn s => , Initialize = fn s => s, InitializeNull = "", IsNull = eq "", Parse = fn s => Some s} type boolGlobal = unit type boolInput = basicState bool val bool : meta (boolGlobal, bool, boolInput) = basic {Display = fn b => {[b]}, Edit = fn s => , Initialize = fn b => b, InitializeNull = False, IsNull = fn _ => False, Parse = fn b => Some b} functor Foreign (M : sig con row :: {Type} con t :: Type val show_t : show t val read_t : read t val eq_t : eq t val inj_t : sql_injectable t con nm :: Name constraint [nm] ~ row table tab : ([nm = t] ++ row) val render : $([nm = t] ++ row) -> string end) = struct open M con global = list (t * string) con input = source string * option (t * $row) val getChoices = List.mapQuery (SELECT * FROM tab AS T) (fn r => (r.T.nm, render r.T)) fun getChoice k = r <- oneRow (SELECT T.{{row}} FROM tab AS T WHERE T.{nm} = {[k]}); return r.T val meta : meta (global, M.t, input) = {Initialize = getChoices, Handlers = fn choices => NonNull ( {Display = fn (_, kr) => case kr of None => error Unexpected Foreign null | Some (k, r) => {[render ({nm = k} ++ r)]}, Edit = fn (s, kr) => {List.mapX (fn (k', rend) => False | Some (k, _) => k' = k}>{[rend]} ) choices} , Initialize = fn k => s <- source (show k); r <- rpc (getChoice k); return (s, Some (k, r)), Parse = fn (s, _) => k <- signal s; return (read k : option t)}, {Display = fn (_, kr) => case kr of None => NULL | Some (k, r) => {[render ({nm = k} ++ r)]}, Edit = fn (s, kr) => True | _ => False}>NULL {List.mapX (fn (k', rend) => False | Some (k, _) => k' = k}>{[rend]} ) choices} , Initialize = fn k => case k of None => s <- source ""; return (s, None) | Some k => s <- source (show k); r <- rpc (getChoice k); return (s, Some (k, r)), Parse = fn (s, _) => ks <- signal s; return (case ks of "" => Some None | _ => case read ks : option t of None => None | Some k => Some (Some k))})} end end con computedState = (unit, xbody) fun computed [row] [t] (_ : show t) name (f : $row -> t) : colMeta row computedState = {Initialize = return (), Handlers = fn () => {Header = name, Project = fn r => return {[f r]}, Update = fn r _ => return r, Display = fn x => x, Edit = fn _ => ..., Validate = fn _ => return True}} fun computedHtml [row] name (f : $row -> xbody) : colMeta row computedState = {Initialize = return (), Handlers = fn () => {Header = name, Project = fn r => return (f r), Update = fn r _ => return r, Display = fn x => x, Edit = fn _ => ..., Validate = fn _ => return True}} functor Make(M : sig con key :: {Type} con row :: {Type} constraint key ~ row table tab : (key ++ row) val raw : $(map rawMeta (key ++ row)) con cols :: {(Type * Type)} val cols : $(map (colMeta (key ++ row)) cols) val keyFolder : folder key val rowFolder : folder row val colsFolder : folder cols con aggregates :: {Type} val aggregates : $(map (aggregateMeta (key ++ row)) aggregates) val aggFolder : folder aggregates end) = struct open Grid.Make(struct fun keyOf r = r --- M.row val list = query (SELECT * FROM {{M.tab}} AS T) (fn r rs => return (r.T :: rs)) [] val wholeRow = @Folder.concat ! M.keyFolder M.rowFolder fun ensql [env] (r : $(M.key ++ M.row)) = map2 [rawMeta] [id] [sql_exp env [] []] (fn [t] meta v => @sql_inject meta.Inj v) [_] wholeRow M.raw r val new = row <- Monad.mapR [rawMeta] [id] (fn [nm :: Name] [t :: Type] meta => meta.New) [_] wholeRow M.raw; dml (insert M.tab (ensql row)); return row fun selector (r : $M.key) : sql_exp [T = M.key ++ M.row] [] [] bool = foldR2 [rawMeta] [id] [fn key => rest :: {Type} -> [rest ~ key] => sql_exp [T = key ++ rest] [] [] bool] (fn [nm :: Name] [t :: Type] [key :: {Type}] [[nm] ~ key] (meta : rawMeta t) (v : t) (exp : rest :: {Type} -> [rest ~ key] => sql_exp [T = key ++ rest] [] [] bool) [rest :: {Type}] [rest ~ [nm = t] ++ key] => (WHERE T.{nm} = {@sql_inject meta.Inj v} AND {exp [[nm = t] ++ rest] !})) (fn [rest :: {Type}] [rest ~ []] => (WHERE TRUE)) [_] M.keyFolder (M.raw --- map rawMeta M.row) r [_] ! fun save key row = dml (update [M.key ++ M.row] ! (ensql row) M.tab (selector key)) fun delete key = dml (Basis.delete M.tab (selector key)) val cols = M.cols val folder = M.colsFolder val aggregates = M.aggregates val aggFolder = M.aggFolder end) end