New linear types syntax: a %p -> b (#18459)

Implements GHC Proposal #356

Updates the haddock submodule.

53 files changed, 110 insertions, 93 deletions

diff --git a/testsuite/tests/linear/should_compile/Linear1Rule.hs b/testsuite/tests/linear/should_compile/Linear1Rule.hs
index 0553c61e84..4a1984c3a0 100644
--- a/testsuite/tests/linear/should_compile/Linear1Rule.hs
+++ b/testsuite/tests/linear/should_compile/Linear1Rule.hs
@@ -2,8 +2,8 @@
 module Linear1Rule where
 
 -- Test the 1 <= p rule
-f :: a #-> b
+f :: a %1 -> b
 f = f
 
-g :: a # p -> b
+g :: a %p -> b
 g x = f x
diff --git a/testsuite/tests/linear/should_compile/LinearConstructors.hs b/testsuite/tests/linear/should_compile/LinearConstructors.hs
index 0e0f1b547e..59886a216b 100644
--- a/testsuite/tests/linear/should_compile/LinearConstructors.hs
+++ b/testsuite/tests/linear/should_compile/LinearConstructors.hs
@@ -4,26 +4,26 @@ module LinearConstructors where
 
 data T a b = MkT a b
 
-f1 :: a #-> b #-> T a b
+f1 :: a %1 -> b %1 -> T a b
 f1 = MkT
 
-f2 :: a #-> b -> T a b
+f2 :: a %1 -> b -> T a b
 f2 = MkT
 
-f3 :: a -> b #-> T a b
+f3 :: a -> b %1 -> T a b
 f3 = MkT
 
 f4 :: a -> b -> T a b
 f4 = MkT
 
 -- tuple sections
-g1 :: a #-> b #-> (a, b, Int)
+g1 :: a %1 -> b %1 -> (a, b, Int)
 g1 = (,,0)
 
-g2 :: a #-> b -> (a, b, Int)
+g2 :: a %1 -> b -> (a, b, Int)
 g2 = (,,0)
 
-g3 :: a -> b #-> (a, b, Int)
+g3 :: a -> b %1 -> (a, b, Int)
 g3 = (,,0)
 
 g4 :: a -> b -> (a, b, Int)
diff --git a/testsuite/tests/linear/should_compile/LinearEmptyCase.hs b/testsuite/tests/linear/should_compile/LinearEmptyCase.hs
index daa1918b56..63bfd017fd 100644
--- a/testsuite/tests/linear/should_compile/LinearEmptyCase.hs
+++ b/testsuite/tests/linear/should_compile/LinearEmptyCase.hs
@@ -4,5 +4,5 @@ module LinearEmptyCase where
 
 data Void
 
-f :: a #-> Void -> b
+f :: a %1 -> Void -> b
 f x y = case y of {}
diff --git a/testsuite/tests/linear/should_compile/LinearGuards.hs b/testsuite/tests/linear/should_compile/LinearGuards.hs
index fae1208176..3ae3f039a5 100644
--- a/testsuite/tests/linear/should_compile/LinearGuards.hs
+++ b/testsuite/tests/linear/should_compile/LinearGuards.hs
@@ -1,6 +1,6 @@
 {-# LANGUAGE LinearTypes #-}
 module LinearGuards where
 
-f :: Bool -> a #-> a
+f :: Bool -> a %1 -> a
 f b a | b = a
       | True = a
diff --git a/testsuite/tests/linear/should_compile/LinearHole.hs b/testsuite/tests/linear/should_compile/LinearHole.hs
index e4c5181d9e..e3016339d1 100644
--- a/testsuite/tests/linear/should_compile/LinearHole.hs
+++ b/testsuite/tests/linear/should_compile/LinearHole.hs
@@ -3,5 +3,5 @@
 
 module LinearHole where  -- #18491
 
-f :: Int #-> Bool #-> Char
+f :: Int %1 -> Bool %1 -> Char
 f x y = _1
diff --git a/testsuite/tests/linear/should_compile/LinearTH2.hs b/testsuite/tests/linear/should_compile/LinearTH2.hs
index a35f9a1c7e..8d3a251c76 100644
--- a/testsuite/tests/linear/should_compile/LinearTH2.hs
+++ b/testsuite/tests/linear/should_compile/LinearTH2.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE LinearTypes, TemplateHaskell, RankNTypes #-}
+{-# LANGUAGE LinearTypes, TemplateHaskell, RankNTypes, NoMonomorphismRestriction #-}
 module LinearTH2 where
 
-x1 = [t|forall p. Int # p -> Int|]
+x1 = [t|forall p. Int %p -> Int|]
diff --git a/testsuite/tests/linear/should_compile/MultConstructor.hs b/testsuite/tests/linear/should_compile/MultConstructor.hs
index 6e631774ba..780c906099 100644
--- a/testsuite/tests/linear/should_compile/MultConstructor.hs
+++ b/testsuite/tests/linear/should_compile/MultConstructor.hs
@@ -4,10 +4,10 @@ module MultConstructor where
 import GHC.Types
 
 data T p a where
-  MkT :: a # p -> T p a
+  MkT :: a %p -> T p a
 
 {-
 this currently fails
-g :: forall (b :: Type). T 'Many b #-> (b,b)
+g :: forall (b :: Type). T 'Many b %1 -> (b,b)
 g (MkT x) = (x,x)
 -}
diff --git a/testsuite/tests/linear/should_compile/OldList.hs b/testsuite/tests/linear/should_compile/OldList.hs
index 2ed7b8aaf2..e84b5bb927 100644
--- a/testsuite/tests/linear/should_compile/OldList.hs
+++ b/testsuite/tests/linear/should_compile/OldList.hs
@@ -24,11 +24,11 @@ sortBy cmp = []
       | a `cmp` b == GT = descending b (a:as) bs
     descending a as bs  = (a:as): sequences bs
 
-    ascending :: a -> (forall i . [a] # i -> [a]) -> [a] -> [[a]]
+    ascending :: a -> (forall i . [a] %i -> [a]) -> [a] -> [[a]]
     ascending a as (b:bs)
       | a `cmp` b /= GT = ascending b foo bs
       where
-        foo :: [a] # k -> [a]
+        foo :: [a] %k -> [a]
         foo ys = as (a:ys)
     ascending a as bs   = let !x = as [a]
                           in x : sequences bs
diff --git a/testsuite/tests/linear/should_compile/Pr110.hs b/testsuite/tests/linear/should_compile/Pr110.hs
index a3311cb7b8..1bce24895f 100644
--- a/testsuite/tests/linear/should_compile/Pr110.hs
+++ b/testsuite/tests/linear/should_compile/Pr110.hs
@@ -3,8 +3,8 @@ module Pr110 where
 
 data Bloop = Bloop Bool
 
-g :: Bloop #-> Bool
+g :: Bloop %1 -> Bool
 g (Bloop x) = x
 
-h :: Bool #-> Bloop
+h :: Bool %1 -> Bloop
 h x = Bloop x
diff --git a/testsuite/tests/linear/should_compile/T18731.hs b/testsuite/tests/linear/should_compile/T18731.hs
index c7899efb54..44a8e8d282 100644
--- a/testsuite/tests/linear/should_compile/T18731.hs
+++ b/testsuite/tests/linear/should_compile/T18731.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE LinearTypes #-}
 module T18731 where
 
-f :: a #-> b
+f :: a %1 -> b
 f x = undefined x
diff --git a/testsuite/tests/linear/should_compile/all.T b/testsuite/tests/linear/should_compile/all.T
index d624a337ba..0fa5750794 100644
--- a/testsuite/tests/linear/should_compile/all.T
+++ b/testsuite/tests/linear/should_compile/all.T
@@ -1,5 +1,3 @@
-broken_multiplicity_syntax = 94  # https://github.com/tweag/ghc/issues/94
-
 test('anf', normal, compile, [''])
 test('Arity2', normal, compile, [''])
 test('Branches', normal, compile, [''])
@@ -10,7 +8,7 @@ test('DollarTest', normal, compile, [''])
 test('Foldr', normal, compile, [''])
 test('Iden', normal, compile, [''])
 test('List', normal, compile, [''])
-test('OldList', expect_broken(broken_multiplicity_syntax), compile, [''])
+test('OldList', normal, compile, [''])
 test('Op', normal, compile, [''])
 test('RankN', normal, compile, [''])
 test('T1735Min', normal, compile, [''])
@@ -28,12 +26,12 @@ test('Linear8', normal, compile, [''])
 test('LinearGuards', normal, compile, [''])
 test('LinearPolyDollar', normal, compile, [''])
 test('LinearConstructors', normal, compile, [''])
-test('Linear1Rule', expect_broken(broken_multiplicity_syntax), compile, [''])
+test('Linear1Rule', normal, compile, [''])
 test('LinearEmptyCase', normal, compile, [''])
 test('Tunboxer', normal, compile, [''])
-test('MultConstructor', expect_broken(broken_multiplicity_syntax), compile, [''])
+test('MultConstructor', normal, compile, [''])
 test('LinearLetRec', expect_broken(405), compile, ['-O -dlinear-core-lint'])
 test('LinearTH1', normal, compile, [''])
-test('LinearTH2', expect_broken(broken_multiplicity_syntax), compile, [''])
+test('LinearTH2', normal, compile, [''])
 test('LinearHole', normal, compile, [''])
 test('T18731', normal, compile, [''])
diff --git a/testsuite/tests/linear/should_fail/Linear13.hs b/testsuite/tests/linear/should_fail/Linear13.hs
index 7b9e09c52b..7d36a33570 100644
--- a/testsuite/tests/linear/should_fail/Linear13.hs
+++ b/testsuite/tests/linear/should_fail/Linear13.hs
@@ -5,7 +5,7 @@ module Linear13 where
 incorrectLet :: a ⊸ ()
 incorrectLet a = let x = a in ()
 
-incorrectLetWithSignature :: (Bool->Bool) #-> ()
+incorrectLetWithSignature :: (Bool->Bool) %1 -> ()
 incorrectLetWithSignature x = let y :: Bool->Bool; y = x in ()
 
 incorrectLazyMatch :: (a,b) ⊸ b
diff --git a/testsuite/tests/linear/should_fail/LinearAsPat.hs b/testsuite/tests/linear/should_fail/LinearAsPat.hs
index e756f4369f..86b557c66b 100644
--- a/testsuite/tests/linear/should_fail/LinearAsPat.hs
+++ b/testsuite/tests/linear/should_fail/LinearAsPat.hs
@@ -2,5 +2,5 @@
 
 module LinearAsPat where
 
-shouldFail :: Bool #-> Bool
+shouldFail :: Bool %1 -> Bool
 shouldFail x@True = x
diff --git a/testsuite/tests/linear/should_fail/LinearBottomMult.hs b/testsuite/tests/linear/should_fail/LinearBottomMult.hs
index 03bf8731a7..b3d00069fe 100644
--- a/testsuite/tests/linear/should_fail/LinearBottomMult.hs
+++ b/testsuite/tests/linear/should_fail/LinearBottomMult.hs
@@ -6,8 +6,8 @@ module LinearBottomMult where
 data Void
 data U a where U :: a -> U a
 
-elim :: U a #-> ()
+elim :: U a %1 -> ()
 elim (U _) = ()
 
-f :: a #-> ()
+f :: a %1 -> ()
 f x = elim (U (\(a :: Void) -> case a of {}))
diff --git a/testsuite/tests/linear/should_fail/LinearConfusedDollar.hs b/testsuite/tests/linear/should_fail/LinearConfusedDollar.hs
index 2cd1628eeb..a679a50431 100644
--- a/testsuite/tests/linear/should_fail/LinearConfusedDollar.hs
+++ b/testsuite/tests/linear/should_fail/LinearConfusedDollar.hs
@@ -5,8 +5,8 @@ module LinearConfusedDollar where
 -- hold anymore. But, as it stands, it produces untyped desugared code, hence
 -- must be rejected.
 
-f :: a #-> a
+f :: a %1 -> a
 f x = x
 
-g :: a #-> a
+g :: a %1 -> a
 g x = f $ x
diff --git a/testsuite/tests/linear/should_fail/LinearConfusedDollar.stderr b/testsuite/tests/linear/should_fail/LinearConfusedDollar.stderr
index 61d7aa2f45..51dc7cdd91 100644
--- a/testsuite/tests/linear/should_fail/LinearConfusedDollar.stderr
+++ b/testsuite/tests/linear/should_fail/LinearConfusedDollar.stderr
@@ -2,7 +2,7 @@
 LinearConfusedDollar.hs:12:7: error:
     • Couldn't match type ‘'One’ with ‘'Many’
       Expected: a -> a
-        Actual: a #-> a
+        Actual: a %1 -> a
     • In the first argument of ‘($)’, namely ‘f’
       In the expression: f $ x
       In an equation for ‘g’: g x = f $ x
diff --git a/testsuite/tests/linear/should_fail/LinearErrOrigin.hs b/testsuite/tests/linear/should_fail/LinearErrOrigin.hs
index 1eeb149959..3368c723b2 100644
--- a/testsuite/tests/linear/should_fail/LinearErrOrigin.hs
+++ b/testsuite/tests/linear/should_fail/LinearErrOrigin.hs
@@ -3,5 +3,5 @@ module LinearErrOrigin where
 
 -- The error message should mention "arising from multiplicity of x".
 
-foo :: (a # p -> b) -> a # q -> b
+foo :: (a %p -> b) -> a %q -> b
 foo f x = f x
diff --git a/testsuite/tests/linear/should_fail/LinearErrOrigin.stderr b/testsuite/tests/linear/should_fail/LinearErrOrigin.stderr
index 10b889a9a8..02dc7216db 100644
--- a/testsuite/tests/linear/should_fail/LinearErrOrigin.stderr
+++ b/testsuite/tests/linear/should_fail/LinearErrOrigin.stderr
@@ -3,14 +3,17 @@ LinearErrOrigin.hs:7:7: error:
     • Couldn't match type ‘p’ with ‘q’ arising from multiplicity of ‘x’
       ‘p’ is a rigid type variable bound by
         the type signature for:
-          foo :: forall a b. (a -> b) -> a -> b
-        at LinearErrOrigin.hs:6:1-35
+          foo :: forall a b (p :: GHC.Types.Multiplicity)
+                        (q :: GHC.Types.Multiplicity).
+                 (a # p -> b) -> a # q -> b
+        at LinearErrOrigin.hs:6:1-31
       ‘q’ is a rigid type variable bound by
         the type signature for:
-          foo :: forall a b. (a -> b) -> a -> b
-        at LinearErrOrigin.hs:6:1-35
+          foo :: forall a b (p :: GHC.Types.Multiplicity)
+                        (q :: GHC.Types.Multiplicity).
+                 (a # p -> b) -> a # q -> b
+        at LinearErrOrigin.hs:6:1-31
     • In an equation for ‘foo’: foo f x = f x
     • Relevant bindings include
         f :: a # p -> b (bound at LinearErrOrigin.hs:7:5)
-        foo :: (a # p -> b) -> a # q -> b
-          (bound at LinearErrOrigin.hs:7:1)
+        foo :: (a # p -> b) -> a # q -> b (bound at LinearErrOrigin.hs:7:1)
diff --git a/testsuite/tests/linear/should_fail/LinearFFI.hs b/testsuite/tests/linear/should_fail/LinearFFI.hs
index 6c6e1c562a..4c58c9eecd 100644
--- a/testsuite/tests/linear/should_fail/LinearFFI.hs
+++ b/testsuite/tests/linear/should_fail/LinearFFI.hs
@@ -3,6 +3,6 @@ module LinearFFI where -- #18472
 
 import Foreign.Ptr
 
-foreign import ccall "exp" c_exp :: Double #-> Double
-foreign import stdcall "dynamic" d8  :: FunPtr (IO Int) #-> IO Int
-foreign import ccall "wrapper" mkF :: IO () #-> IO (FunPtr (IO ()))
+foreign import ccall "exp" c_exp :: Double %1 -> Double
+foreign import stdcall "dynamic" d8  :: FunPtr (IO Int) %1 -> IO Int
+foreign import ccall "wrapper" mkF :: IO () %1 -> IO (FunPtr (IO ()))
diff --git a/testsuite/tests/linear/should_fail/LinearFFI.stderr b/testsuite/tests/linear/should_fail/LinearFFI.stderr
index 41dd5e66a7..6d0707252e 100644
--- a/testsuite/tests/linear/should_fail/LinearFFI.stderr
+++ b/testsuite/tests/linear/should_fail/LinearFFI.stderr
@@ -3,18 +3,18 @@ LinearFFI.hs:6:1: error:
     • Unacceptable argument type in foreign declaration:
         Linear types are not supported in FFI declarations, see #18472
     • When checking declaration:
-        foreign import ccall safe "exp" c_exp :: Double #-> Double
+        foreign import ccall safe "exp" c_exp :: Double %1 -> Double
 
 LinearFFI.hs:7:1: error:
     • Unacceptable argument type in foreign declaration:
         Linear types are not supported in FFI declarations, see #18472
     • When checking declaration:
         foreign import stdcall safe "dynamic" d8
-          :: FunPtr (IO Int) #-> IO Int
+          :: FunPtr (IO Int) %1 -> IO Int
 
 LinearFFI.hs:8:1: error:
     • Unacceptable argument type in foreign declaration:
         Linear types are not supported in FFI declarations, see #18472
     • When checking declaration:
         foreign import ccall safe "wrapper" mkF
-          :: IO () #-> IO (FunPtr (IO ()))
+          :: IO () %1 -> IO (FunPtr (IO ()))
diff --git a/testsuite/tests/linear/should_fail/LinearIf.hs b/testsuite/tests/linear/should_fail/LinearIf.hs
index b19873120c..9ddd5ce50b 100644
--- a/testsuite/tests/linear/should_fail/LinearIf.hs
+++ b/testsuite/tests/linear/should_fail/LinearIf.hs
@@ -9,7 +9,7 @@ ifThenElse :: Bool -> a -> a -> a
 ifThenElse True x _ = x
 ifThenElse False _ y = y
 
-f :: Bool #-> Char #-> Char #-> Char
+f :: Bool %1 -> Char %1 -> Char %1 -> Char
 f b x y = if b then x else y
   -- 'f' ought to be unrestricted in all three arguments because it desugars to
   -- > ifThenElse b x y
diff --git a/testsuite/tests/linear/should_fail/LinearKind.hs b/testsuite/tests/linear/should_fail/LinearKind.hs
index a60554a7a7..6455249c6c 100644
--- a/testsuite/tests/linear/should_fail/LinearKind.hs
+++ b/testsuite/tests/linear/should_fail/LinearKind.hs
@@ -1,4 +1,4 @@
 {-# LANGUAGE LinearTypes, KindSignatures #-}
 module LinearKind where
 
-data A :: * #-> *
+data A :: * %1 -> *
diff --git a/testsuite/tests/linear/should_fail/LinearKind.stderr b/testsuite/tests/linear/should_fail/LinearKind.stderr
index 5ac2825b21..9ba3f744cf 100644
--- a/testsuite/tests/linear/should_fail/LinearKind.stderr
+++ b/testsuite/tests/linear/should_fail/LinearKind.stderr
@@ -1,5 +1,5 @@
 
 LinearKind.hs:4:11: error:
-    • Linear arrows disallowed in kinds: * #-> *
-    • In the kind ‘* #-> *’
+    • Linear arrows disallowed in kinds: * %1 -> *
+    • In the kind ‘* %1 -> *’
       In the data type declaration for ‘A’
diff --git a/testsuite/tests/linear/should_fail/LinearLazyPat.hs b/testsuite/tests/linear/should_fail/LinearLazyPat.hs
index 8ed4024c40..be87629cc9 100644
--- a/testsuite/tests/linear/should_fail/LinearLazyPat.hs
+++ b/testsuite/tests/linear/should_fail/LinearLazyPat.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE LinearTypes #-}
 module LinearLazyPat where
 
-f :: (a,b) #-> (b,a)
+f :: (a,b) %1 -> (b,a)
 f ~(x,y) = (y,x)
diff --git a/testsuite/tests/linear/should_fail/LinearLet.hs b/testsuite/tests/linear/should_fail/LinearLet.hs
index bf822a8a6e..9ad7f4932f 100644
--- a/testsuite/tests/linear/should_fail/LinearLet.hs
+++ b/testsuite/tests/linear/should_fail/LinearLet.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE LinearTypes #-}
 module LinearLet where
 
-f :: a #-> (a,a)
+f :: a %1 -> (a,a)
 f x = let y = x in (y,y)
diff --git a/testsuite/tests/linear/should_fail/LinearNoExt.hs b/testsuite/tests/linear/should_fail/LinearNoExt.hs
index 2671246f21..47c3ea85f9 100644
--- a/testsuite/tests/linear/should_fail/LinearNoExt.hs
+++ b/testsuite/tests/linear/should_fail/LinearNoExt.hs
@@ -1,3 +1,3 @@
 module LinearNoExt where
 
-type T = a #-> a
+type T a = a %1 -> a
diff --git a/testsuite/tests/linear/should_fail/LinearNoExt.stderr b/testsuite/tests/linear/should_fail/LinearNoExt.stderr
index 452409586d..9277e29ea5 100644
--- a/testsuite/tests/linear/should_fail/LinearNoExt.stderr
+++ b/testsuite/tests/linear/should_fail/LinearNoExt.stderr
@@ -1,3 +1,10 @@
 
-LinearNoExt.hs:3:12: error:
-    Enable LinearTypes to allow linear functions
+LinearNoExt.hs:3:14: error:
+    Not in scope: type constructor or class ‘%’
+
+LinearNoExt.hs:3:14: error:
+    Illegal operator ‘%’ in type ‘a % 1’
+      Use TypeOperators to allow operators in types
+
+LinearNoExt.hs:3:15: error:
+    Illegal type: ‘1’ Perhaps you intended to use DataKinds
diff --git a/testsuite/tests/linear/should_fail/LinearNoExtU.hs b/testsuite/tests/linear/should_fail/LinearNoExtU.hs
new file mode 100644
index 0000000000..1e7ffad4e8
--- /dev/null
+++ b/testsuite/tests/linear/should_fail/LinearNoExtU.hs
@@ -0,0 +1,4 @@
+{-# LANGUAGE UnicodeSyntax #-}
+module LinearNoExtU where
+
+type T a = a ⊸ a
diff --git a/testsuite/tests/linear/should_fail/LinearNoExtU.stderr b/testsuite/tests/linear/should_fail/LinearNoExtU.stderr
new file mode 100644
index 0000000000..ac187aee4a
--- /dev/null
+++ b/testsuite/tests/linear/should_fail/LinearNoExtU.stderr
@@ -0,0 +1,3 @@
+
+LinearNoExtU.hs:4:14: error:
+    Enable LinearTypes to allow linear functions
diff --git a/testsuite/tests/linear/should_fail/LinearPartialSig.hs b/testsuite/tests/linear/should_fail/LinearPartialSig.hs
index 01dbeddfba..cbda746317 100644
--- a/testsuite/tests/linear/should_fail/LinearPartialSig.hs
+++ b/testsuite/tests/linear/should_fail/LinearPartialSig.hs
@@ -2,5 +2,5 @@
 module LinearPartialSig where
 
 -- We should suggest that _ :: Multiplicity
-f :: a # _ -> a
+f :: a %_ -> a
 f x = x
diff --git a/testsuite/tests/linear/should_fail/LinearPartialSig.stderr b/testsuite/tests/linear/should_fail/LinearPartialSig.stderr
index 4d25260bf2..704fcb258c 100644
--- a/testsuite/tests/linear/should_fail/LinearPartialSig.stderr
+++ b/testsuite/tests/linear/should_fail/LinearPartialSig.stderr
@@ -1,5 +1,5 @@
 
-LinearPartialSig.hs:5:13: error:
+LinearPartialSig.hs:5:9: error:
     • Found type wildcard ‘_’
         standing for ‘'Many :: GHC.Types.Multiplicity’
       To use the inferred type, enable PartialTypeSignatures
diff --git a/testsuite/tests/linear/should_fail/LinearPatSyn.hs b/testsuite/tests/linear/should_fail/LinearPatSyn.hs
index 3e947dba2e..3e87bfc078 100644
--- a/testsuite/tests/linear/should_fail/LinearPatSyn.hs
+++ b/testsuite/tests/linear/should_fail/LinearPatSyn.hs
@@ -7,8 +7,8 @@ module LinearPatSyn where
 -- seems to require changes to the desugarer. So currently pattern synonyms are
 -- disallowed in linear patterns.
 
-pattern P :: b #-> a #-> (a, b)
+pattern P :: b %1 -> a %1 -> (a, b)
 pattern P y x = (x, y)
 
-s :: (a, b) #-> (b, a)
+s :: (a, b) %1 -> (b, a)
 s (P y x) = (y, x)
diff --git a/testsuite/tests/linear/should_fail/LinearPatternGuardWildcard.hs b/testsuite/tests/linear/should_fail/LinearPatternGuardWildcard.hs
index be837fd80b..de04b28f49 100644
--- a/testsuite/tests/linear/should_fail/LinearPatternGuardWildcard.hs
+++ b/testsuite/tests/linear/should_fail/LinearPatternGuardWildcard.hs
@@ -3,5 +3,5 @@ module LinearPatternGuardWildcard where
 
 -- See #18439
 
-unsafeConsume :: a #-> ()
+unsafeConsume :: a %1 -> ()
 unsafeConsume x | _ <- x = ()
diff --git a/testsuite/tests/linear/should_fail/LinearPolyType.hs b/testsuite/tests/linear/should_fail/LinearPolyType.hs
index bcf46eed9f..21c09247b5 100644
--- a/testsuite/tests/linear/should_fail/LinearPolyType.hs
+++ b/testsuite/tests/linear/should_fail/LinearPolyType.hs
@@ -11,6 +11,6 @@ type family If b t f where
   If True t _ = t
   If False _ f = f
 
-dep :: SBool b -> Int # If b One Many -> Int
+dep :: SBool b -> Int %(If b One Many) -> Int
 dep STrue x = x
 dep SFalse _ = 0
diff --git a/testsuite/tests/linear/should_fail/LinearPolyType.stderr b/testsuite/tests/linear/should_fail/LinearPolyType.stderr
index fab6dfcc9b..884b8991fb 100644
--- a/testsuite/tests/linear/should_fail/LinearPolyType.stderr
+++ b/testsuite/tests/linear/should_fail/LinearPolyType.stderr
@@ -1,3 +1,6 @@
 
 LinearPolyType.hs:15:1: error:
     Multiplicity coercions are currently not supported
+
+LinearPolyType.hs:15:1: error:
+    Multiplicity coercions are currently not supported
diff --git a/testsuite/tests/linear/should_fail/LinearRecordUpdate.hs b/testsuite/tests/linear/should_fail/LinearRecordUpdate.hs
index e143dbd604..c9df293624 100644
--- a/testsuite/tests/linear/should_fail/LinearRecordUpdate.hs
+++ b/testsuite/tests/linear/should_fail/LinearRecordUpdate.hs
@@ -4,5 +4,5 @@ module LinearRecordUpdate where
 
 data R = R { x :: Int, y :: Bool }
 
-shouldFail :: R #-> R
+shouldFail :: R %1 -> R
 shouldFail r = r { y = False }
diff --git a/testsuite/tests/linear/should_fail/LinearSeq.hs b/testsuite/tests/linear/should_fail/LinearSeq.hs
index 0f2ed39c93..efe102c510 100644
--- a/testsuite/tests/linear/should_fail/LinearSeq.hs
+++ b/testsuite/tests/linear/should_fail/LinearSeq.hs
@@ -2,5 +2,5 @@
 
 module LinearSeq where
 
-bad :: a #-> ()
+bad :: a %1 -> ()
 bad x = seq x ()
diff --git a/testsuite/tests/linear/should_fail/LinearSequenceExpr.hs b/testsuite/tests/linear/should_fail/LinearSequenceExpr.hs
index ff3ac9cedb..2643c78252 100644
--- a/testsuite/tests/linear/should_fail/LinearSequenceExpr.hs
+++ b/testsuite/tests/linear/should_fail/LinearSequenceExpr.hs
@@ -3,6 +3,6 @@
 
 module LinearSequenceExpr where
 
-f :: Char #-> Char #-> [Char]
+f :: Char %1 -> Char %1 -> [Char]
 f x y = [x .. y]
 -- This ought to fail, because `fromList` in base, is unrestricted
diff --git a/testsuite/tests/linear/should_fail/LinearVar.hs b/testsuite/tests/linear/should_fail/LinearVar.hs
index 7b4cde3647..9a3abb8c89 100644
--- a/testsuite/tests/linear/should_fail/LinearVar.hs
+++ b/testsuite/tests/linear/should_fail/LinearVar.hs
@@ -1,5 +1,5 @@
 {-# LANGUAGE LinearTypes #-}
 module LinearVar where
 
-f :: a # m -> b
+f :: a %m -> b
 f = undefined :: a -> b
diff --git a/testsuite/tests/linear/should_fail/LinearVar.stderr b/testsuite/tests/linear/should_fail/LinearVar.stderr
index 04014ce79b..cdbb4de1c9 100644
--- a/testsuite/tests/linear/should_fail/LinearVar.stderr
+++ b/testsuite/tests/linear/should_fail/LinearVar.stderr
@@ -1,12 +1,12 @@
 
 LinearVar.hs:5:5: error:
     • Couldn't match type ‘m’ with ‘'Many’
+      Expected: a # m -> b
+        Actual: a -> b
       ‘m’ is a rigid type variable bound by
         the type signature for:
-          f :: forall a b. a -> b
-        at LinearVar.hs:4:1-16
-      Expected type: a # m -> b
-        Actual type: a -> b
+          f :: forall a b (m :: GHC.Types.Multiplicity). a # m -> b
+        at LinearVar.hs:4:1-14
     • In the expression: undefined :: a -> b
       In an equation for ‘f’: f = undefined :: a -> b
     • Relevant bindings include
diff --git a/testsuite/tests/linear/should_fail/LinearViewPattern.hs b/testsuite/tests/linear/should_fail/LinearViewPattern.hs
index 737393911b..55058e4263 100644
--- a/testsuite/tests/linear/should_fail/LinearViewPattern.hs
+++ b/testsuite/tests/linear/should_fail/LinearViewPattern.hs
@@ -7,5 +7,5 @@ module LinearViewPattern where
 -- incorrect Core being emitted by the desugarer. When we understand linear view
 -- pattern better, we will probably want to remove this test.
 
-f :: Bool #-> Bool
+f :: Bool %1 -> Bool
 f (not -> True) = True
diff --git a/testsuite/tests/linear/should_fail/all.T b/testsuite/tests/linear/should_fail/all.T
index 5a79b031b6..bcba344268 100644
--- a/testsuite/tests/linear/should_fail/all.T
+++ b/testsuite/tests/linear/should_fail/all.T
@@ -1,5 +1,3 @@
-broken_multiplicity_syntax = 94  # https://github.com/tweag/ghc/issues/94
-
 test('TypeClass', normal, compile_fail, [''])
 test('Linear11', normal, compile_fail, [''])
 test('Linear13', normal, compile_fail, [''])
@@ -10,6 +8,7 @@ test('Linear5', normal, compile_fail, [''])
 test('Linear7', normal, compile_fail, [''])
 test('Linear9', normal, compile_fail, [''])
 test('LinearNoExt', normal, compile_fail, [''])
+test('LinearNoExtU', normal, compile_fail, [''])
 test('LinearAsPat', normal, compile_fail, [''])
 test('LinearLet', normal, compile_fail, [''])
 test('LinearLazyPat', normal, compile_fail, [''])
@@ -19,11 +18,11 @@ test('LinearViewPattern', normal, compile_fail, [''])
 test('LinearConfusedDollar', normal, compile_fail, [''])
 test('LinearPatSyn', normal, compile_fail, [''])
 test('LinearGADTNewtype', normal, compile_fail, [''])
-test('LinearPartialSig', expect_broken(broken_multiplicity_syntax), compile_fail, [''])
+test('LinearPartialSig', normal, compile_fail, [''])
 test('LinearKind', normal, compile_fail, [''])
-test('LinearVar', expect_broken(broken_multiplicity_syntax), compile_fail, [''])
-test('LinearErrOrigin', expect_broken(broken_multiplicity_syntax), compile_fail, [''])
-test('LinearPolyType', expect_broken([436, broken_multiplicity_syntax]), compile_fail, [''])  # not supported yet (#354)
+test('LinearVar', normal, compile_fail, ['-XLinearTypes'])
+test('LinearErrOrigin', normal, compile_fail, ['-XLinearTypes'])
+test('LinearPolyType', normal, compile_fail, [''])  # not supported yet (#390)
 test('LinearBottomMult', normal, compile_fail, [''])
 test('LinearSequenceExpr', normal, compile_fail, [''])
 test('LinearIf', normal, compile_fail, [''])
diff --git a/testsuite/tests/linear/should_run/LinearGhci.script b/testsuite/tests/linear/should_run/LinearGhci.script
index cd55fe73bd..b8fa13a4ca 100644
--- a/testsuite/tests/linear/should_run/LinearGhci.script
+++ b/testsuite/tests/linear/should_run/LinearGhci.script
@@ -3,7 +3,7 @@ data T a = MkT a
 :set -XLinearTypes
 :type MkT
 :set -XGADTs
-data T a where MkT :: a #-> a -> T a
+data T a where MkT :: a %1 -> a -> T a
 :info T
 data T a b m n r = MkT a b m n r
 :set -fprint-explicit-foralls
diff --git a/testsuite/tests/linear/should_run/LinearGhci.stdout b/testsuite/tests/linear/should_run/LinearGhci.stdout
index ed5c9cfe64..29cfa88b11 100644
--- a/testsuite/tests/linear/should_run/LinearGhci.stdout
+++ b/testsuite/tests/linear/should_run/LinearGhci.stdout
@@ -2,6 +2,6 @@ MkT :: a -> T a
 MkT :: a -> T a
 type T :: * -> *
 data T a where
-  MkT :: a #-> a -> T a
+  MkT :: a %1 -> a -> T a
   	-- Defined at <interactive>:6:1
 MkT :: forall a b m n r. a -> b -> m -> n -> r -> T a b m n r
diff --git a/testsuite/tests/linear/should_run/LinearTypeable.hs b/testsuite/tests/linear/should_run/LinearTypeable.hs
index 69772f7b33..f22d6c445a 100644
--- a/testsuite/tests/linear/should_run/LinearTypeable.hs
+++ b/testsuite/tests/linear/should_run/LinearTypeable.hs
@@ -4,7 +4,7 @@ module Main (main) where
 import Data.Typeable
 import Data.Maybe
 
-x :: Maybe ((Int -> Int) :~: (Int #-> Int))
+x :: Maybe ((Int -> Int) :~: (Int %1 -> Int))
 x = eqT
 
 main = print (isJust x)
diff --git a/testsuite/tests/qualifieddo/should_run/Monad/Linear.hs b/testsuite/tests/qualifieddo/should_run/Monad/Linear.hs
index df7f2775c8..05eadd3d04 100644
--- a/testsuite/tests/qualifieddo/should_run/Monad/Linear.hs
+++ b/testsuite/tests/qualifieddo/should_run/Monad/Linear.hs
@@ -8,10 +8,10 @@ data T where T :: Int -> T
 data TM a = TM a
 
 class Monad m where
-  return :: a #-> m a
-  (>>=) :: m a #-> (a #-> m b) #-> m b
+  return :: a %1 -> m a
+  (>>=) :: m a %1 -> (a %1 -> m b) %1 -> m b
 
-(>>) :: Monad m => m () #-> m b #-> m b
+(>>) :: Monad m => m () %1 -> m b %1 -> m b
 m1 >> m2 = m1 >>= \() -> m2
 
 instance Monad TM where
@@ -27,11 +27,11 @@ runTM (TM (Unrestricted a)) = a
 newT :: TM T
 newT = return (T 0)
 
-increaseT :: T #-> TM T
+increaseT :: T %1 -> TM T
 increaseT (T i) = return (T (i+1))
 
-extractT :: T #-> TM (T, Unrestricted Int)
+extractT :: T %1 -> TM (T, Unrestricted Int)
 extractT (T i) = return (T i, Unrestricted i)
 
-deleteT :: T #-> TM ()
+deleteT :: T %1 -> TM ()
 deleteT (T _) = return ()
diff --git a/testsuite/tests/simplCore/should_compile/T7360.stderr b/testsuite/tests/simplCore/should_compile/T7360.stderr
index ccf2147977..6958eceeca 100644
--- a/testsuite/tests/simplCore/should_compile/T7360.stderr
+++ b/testsuite/tests/simplCore/should_compile/T7360.stderr
@@ -4,7 +4,7 @@ Result size of Tidy Core
   = {terms: 106, types: 47, coercions: 0, joins: 0/0}
 
 -- RHS size: {terms: 6, types: 3, coercions: 0, joins: 0/0}
-T7360.$WFoo3 [InlPrag=INLINE[final] CONLIKE] :: Int #-> Foo
+T7360.$WFoo3 [InlPrag=INLINE[final] CONLIKE] :: Int %1 -> Foo
 [GblId[DataConWrapper],
  Arity=1,
  Caf=NoCafRefs,
diff --git a/testsuite/tests/stranal/should_compile/T16029.stdout b/testsuite/tests/stranal/should_compile/T16029.stdout
index 5b3a03a603..59507ee4ce 100644
--- a/testsuite/tests/stranal/should_compile/T16029.stdout
+++ b/testsuite/tests/stranal/should_compile/T16029.stdout
@@ -1,4 +1,4 @@
-T16029.$WMkT [InlPrag=INLINE[final] CONLIKE] :: Int #-> Int #-> T
+  :: Int %1 -> Int %1 -> T
          Tmpl= \ (dt [Occ=Once1!] :: Int) (dt [Occ=Once1!] :: Int) ->
   = \ (dt [Occ=Once1!] :: Int) (dt [Occ=Once1!] :: Int) ->
   :: GHC.Prim.Int# -> GHC.Prim.Int#
diff --git a/testsuite/tests/th/T10019.stdout b/testsuite/tests/th/T10019.stdout
index 6acec6d98f..85510c1af1 100644
--- a/testsuite/tests/th/T10019.stdout
+++ b/testsuite/tests/th/T10019.stdout
@@ -1 +1 @@
-"Constructor from Ghci1.Option: Ghci1.Some :: forall (a_0 :: *) .\n                                             a_0 #-> Ghci1.Option a_0"
+"Constructor from Ghci1.Option: Ghci1.Some :: forall (a_0 :: *) .\n                                             a_0 %1 -> Ghci1.Option a_0"
diff --git a/testsuite/tests/th/T11345.stdout b/testsuite/tests/th/T11345.stdout
index f710d847c8..782005a4fb 100644
--- a/testsuite/tests/th/T11345.stdout
+++ b/testsuite/tests/th/T11345.stdout
@@ -3,8 +3,8 @@ data Main.GADT (a_0 :: *) where
                    GHC.Types.Int -> Main.GADT GHC.Types.Int
     (Main.:***:) :: GHC.Types.Int ->
                     GHC.Types.Int -> Main.GADT GHC.Types.Int
-Constructor from Main.GADT: (Main.:***:) :: GHC.Types.Int #->
-                                            GHC.Types.Int #-> Main.GADT GHC.Types.Int
+Constructor from Main.GADT: (Main.:***:) :: GHC.Types.Int %1 ->
+                                            GHC.Types.Int %1 -> Main.GADT GHC.Types.Int
 Nothing
 Just (Fixity 7 InfixR)
 1 :****: 4
diff --git a/testsuite/tests/th/TH_reifyLinear.hs b/testsuite/tests/th/TH_reifyLinear.hs
index c551ad9235..3a99dc79a6 100644
--- a/testsuite/tests/th/TH_reifyLinear.hs
+++ b/testsuite/tests/th/TH_reifyLinear.hs
@@ -4,7 +4,7 @@ module TH_reifyLinear where
 import Language.Haskell.TH
 import System.IO
 
-type T = Int #-> Int
+type T = Int %1 -> Int
 
 $(
     do x <- reify ''T
diff --git a/testsuite/tests/th/TH_reifyLinear.stderr b/testsuite/tests/th/TH_reifyLinear.stderr
index ed7866bfa8..5f2cceb12a 100644
--- a/testsuite/tests/th/TH_reifyLinear.stderr
+++ b/testsuite/tests/th/TH_reifyLinear.stderr
@@ -1 +1 @@
-type TH_reifyLinear.T = GHC.Types.Int #-> GHC.Types.Int
+type TH_reifyLinear.T = GHC.Types.Int %1 -> GHC.Types.Int
diff --git a/testsuite/tests/typecheck/should_fail/T15807.stderr b/testsuite/tests/typecheck/should_fail/T15807.stderr
index bac4b5596e..8589ec1268 100644
--- a/testsuite/tests/typecheck/should_fail/T15807.stderr
+++ b/testsuite/tests/typecheck/should_fail/T15807.stderr
@@ -2,7 +2,7 @@
 T15807.hs:12:3: error:
     • Cannot generalise type; skolem ‘f’ would escape its scope
       if I tried to quantify (f0 :: f -> *) in this type:
-        forall f (a :: f). f a #-> App @f @f0 a
+        forall f (a :: f). f a %1 -> App @f @f0 a
       (Indeed, I sometimes struggle even printing this correctly,
        due to its ill-scoped nature.)
     • In the definition of data constructor ‘MkApp’