CurryInfo: ertools-3.0.0 / Database.ERD.Generic.requiredForeignDBKey
definition: 
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requiredForeignDBKey :: (Read t, Show t, Eq k, Show k) =>
String -> (Key -> t -> Dynamic) -> (Key -> t -> en)
-> (en -> k) -> k -> Transaction ()
requiredForeignDBKey ename entrypred info2entry keyf key =
getDB (getAllEntities entrypred info2entry) |>>= \ens ->
if null (filter (\e -> keyf e == key) ens)
then doneT
else errorT (TError KeyRequiredError
("key: "++show key ++ " required in table: " ++ ename))
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demand:
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no demanded arguments |
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deterministic:
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deterministic operation |
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documentation:
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If a given key occurs in a (foreign key) attribute of an entity, raise a transaction error. |
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failfree:
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<FAILING> |
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indeterministic:
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referentially transparent operation |
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infix:
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no fixity defined |
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iotype:
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{(_,_,_,_,_,_,_,_,_) |-> _}
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name:
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requiredForeignDBKey |
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precedence:
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no precedence defined |
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result-values:
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_ |
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signature:
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(Prelude.Read a, Prelude.Show a, Prelude.Eq c, Prelude.Show c) => String -> (Prelude.Int -> a -> Database.KeyDatabaseSQLite.Dynamic) -> (Prelude.Int -> a -> b) -> (b -> c) -> c -> Database.KeyDatabaseSQLite.Transaction () |
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solution-complete:
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operation might suspend on free variables |
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terminating:
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possibly non-terminating |
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totally-defined:
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possibly non-reducible on same data term |