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What fixity does `~` has?

Prelude Data.Type.Equality> :i :~:
...
infix 4 :~:

yet

Prelude Data.Type.Equality> :i (~)
...
-- says nothing

I'd expect them to have similar fixity.

Having ~ bind less tight then e.g. GHC.TypeLits.+ (infixl 6) would be very nice.

Prelude Data.Type.Equality GHC.TypeLits> :kind! 5 + 5 :~: 10
5 + 5 :~: 10 :: *
= 10 :~: 10
Prelude Data.Type.Equality GHC.TypeLits> :kind! 5 + 5 ~ 10

<interactive>:1:5: error:
    • Expected kind ‘Nat’, but ‘5 ~ 10’ has kind ‘Constraint’
    • In the second argument of ‘(+)’, namely ‘5 ~ 10’
      In the type ‘5 + 5 ~ 10’
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