eee3b89 · squeal · git.iko.soy

git.iko.soy/squeal

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more function notation

eee3b89Eitan Chatav8 years ago

squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+25−30

compare with dev

unifiedsplit

@@ -295,33 +295,45 @@ newtype Expression

295instance RenderSQL (Expression outer grp commons schemas params from ty) where

296 renderSQL = renderExpression

297

298+-- | An `Expr` is a closed `Expression`.

298type Expr x

299type Expr x

299 = forall outer grp commons schemas params from

300 = forall outer grp commons schemas params from

300 . Expression outer grp commons schemas params from x

301 . Expression outer grp commons schemas params from x

302+ -- ^ cannot reference aliases

301

303

302type Operator x1 x2 y

304type Operator x1 x2 y

303 = forall outer grp commons schemas params from

305 = forall outer grp commons schemas params from

304 . Expression outer grp commons schemas params from x1

306 . Expression outer grp commons schemas params from x1

307+ -- ^ left input

305 -> Expression outer grp commons schemas params from x2

308 -> Expression outer grp commons schemas params from x2

309+ -- ^ right input

306 -> Expression outer grp commons schemas params from y

310 -> Expression outer grp commons schemas params from y

311+ -- ^ output

307

312

308type (:-->) x y

313type (:-->) x y

309 = forall outer grp commons schemas params from

314 = forall outer grp commons schemas params from

310 . Expression outer grp commons schemas params from x

315 . Expression outer grp commons schemas params from x

316+ -- ^ input

311 -> Expression outer grp commons schemas params from y

317 -> Expression outer grp commons schemas params from y

318+ -- ^ output

312

319

313type FunctionHet xs y

320type FunctionHet xs y

314 = forall outer grp commons schemas params from

321 = forall outer grp commons schemas params from

315 . NP (Expression outer grp commons schemas params from) xs

322 . NP (Expression outer grp commons schemas params from) xs

323+ -- ^ inputs

316 -> Expression outer grp commons schemas params from y

324 -> Expression outer grp commons schemas params from y

325+ -- ^ output

317

326

318−type FunctionHom x y

327+type FunctionHom x0 x1 y

319 = forall outer grp commons schemas params from

328 = forall outer grp commons schemas params from

320− . [Expression outer grp commons schemas params from x]

329+ . [Expression outer grp commons schemas params from x0]

330+ -- ^ inputs

321− -> Expression outer grp commons schemas params from x

331+ -> Expression outer grp commons schemas params from x1

332+ -- ^ must have at least 1 input

322 -> Expression outer grp commons schemas params from y

333 -> Expression outer grp commons schemas params from y

334+ -- ^ output

323

335

324−unsafeFunctionHom :: ByteString -> FunctionHom x y

336+unsafeFunctionHom :: ByteString -> FunctionHom x0 x1 y

325unsafeFunctionHom fun xs x = UnsafeExpression $ fun <> parenthesized

337unsafeFunctionHom fun xs x = UnsafeExpression $ fun <> parenthesized

326 (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)

338 (commaSeparated (renderSQL <$> xs) <> ", " <> renderSQL x)

327

339

@@ -479,12 +491,7 @@ notNull = UnsafeExpression . renderSQL

479--

491--

480-- >>> printSQL $ coalesce [null_, true] false

492-- >>> printSQL $ coalesce [null_, true] false

481-- COALESCE(NULL, TRUE, FALSE)

493-- COALESCE(NULL, TRUE, FALSE)

482−coalesce

494+coalesce :: FunctionHom ('Null ty) ('NotNull ty) ('NotNull ty)

483− :: [Expression outer grp commons schemas params from ('Null ty)]

484− -- ^ @NULL@s may be present

485− -> Expression outer grp commons schemas params from ('NotNull ty)

486− -- ^ @NULL@ is absent

487− -> Expression outer grp commons schemas params from ('NotNull ty)

488coalesce nullxs notNullx = UnsafeExpression $

495coalesce nullxs notNullx = UnsafeExpression $

489 "COALESCE" <> parenthesized (commaSeparated

496 "COALESCE" <> parenthesized (commaSeparated

490 ((renderSQL <$> nullxs) <> [renderSQL notNullx]))

497 ((renderSQL <$> nullxs) <> [renderSQL notNullx]))

@@ -502,18 +509,12 @@ fromNull notNullx nullx = coalesce [nullx] notNullx

502

509

503-- | >>> printSQL $ null_ & isNull

510-- | >>> printSQL $ null_ & isNull

504-- NULL IS NULL

511-- NULL IS NULL

505−isNull

512+isNull :: 'Null ty :--> null 'PGbool

506− :: Expression outer grp commons schemas params from ('Null ty)

507− -- ^ possibly @NULL@

508− -> Condition outer grp commons schemas params from

509isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"

513isNull x = UnsafeExpression $ renderSQL x <+> "IS NULL"

510

514

511-- | >>> printSQL $ null_ & isNotNull

515-- | >>> printSQL $ null_ & isNotNull

512-- NULL IS NOT NULL

516-- NULL IS NOT NULL

513−isNotNull

517+isNotNull :: 'Null ty :--> null 'PGbool

514− :: Expression outer grp commons schemas params from ('Null ty)

515− -- ^ possibly @NULL@

516− -> Condition outer grp commons schemas params from

517isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"

518isNotNull x = UnsafeExpression $ renderSQL x <+> "IS NOT NULL"

518

519

519-- | analagous to `maybe` using @IS NULL@

520-- | analagous to `maybe` using @IS NULL@

@@ -535,18 +536,12 @@ matchNull y f x = ifThenElse (isNull x) y

535`nullIf` gives @NULL@.

536`nullIf` gives @NULL@.

536

537

537>>> :set -XTypeApplications -XDataKinds

538>>> :set -XTypeApplications -XDataKinds

538−>>> let expr = nullIf false (param @1) :: Expression outer grp commons schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)

539+>>> let expr = nullIf (false *: param @1) :: Expression outer grp commons schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)

539>>> printSQL expr

540>>> printSQL expr

540−NULL IF (FALSE, ($1 :: bool))

541+NULLIF(FALSE, ($1 :: bool))

541-}

542-}

542−nullIf

543+nullIf :: FunctionHet '[ 'NotNull ty, 'NotNull ty] ('Null ty)

543− :: Expression outer grp commons schemas params from ('NotNull ty)

544+nullIf = functionHet "NULLIF"

544− -- ^ @NULL@ is absent

545− -> Expression outer grp commons schemas params from ('NotNull ty)

546− -- ^ @NULL@ is absent

547− -> Expression outer grp commons schemas params from ('Null ty)

548−nullIf x y = UnsafeExpression $ "NULL IF" <+> parenthesized

549− (renderSQL x <> ", " <> renderSQL y)

550

545

551-- | >>> printSQL $ array [null_, false, true]

546-- | >>> printSQL $ array [null_, false, true]

552-- ARRAY[NULL, FALSE, TRUE]

547-- ARRAY[NULL, FALSE, TRUE]

@@ -628,12 +623,12 @@ instance Monoid

628-- | >>> let expr = greatest [param @1] currentTimestamp :: Expression outer grp commons schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)

623-- | >>> let expr = greatest [param @1] currentTimestamp :: Expression outer grp commons schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)

629-- >>> printSQL expr

624-- >>> printSQL expr

630-- GREATEST(($1 :: timestamp with time zone), CURRENT_TIMESTAMP)

625-- GREATEST(($1 :: timestamp with time zone), CURRENT_TIMESTAMP)

631−greatest :: FunctionHom ty ty

626+greatest :: FunctionHom ty ty ty

632greatest = unsafeFunctionHom "GREATEST"

627greatest = unsafeFunctionHom "GREATEST"

633

628

634-- | >>> printSQL $ least [null_] currentTimestamp

629-- | >>> printSQL $ least [null_] currentTimestamp

635-- LEAST(NULL, CURRENT_TIMESTAMP)

630-- LEAST(NULL, CURRENT_TIMESTAMP)

636−least :: FunctionHom ty ty

631+least :: FunctionHom ty ty ty

637least = unsafeFunctionHom "LEAST"

632least = unsafeFunctionHom "LEAST"

638

633

639-- | >>> printSQL $ unsafeBinaryOp "OR" true false

634-- | >>> printSQL $ unsafeBinaryOp "OR" true false