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https://github.com/idris-lang/Idris2.git
synced 2024-12-19 09:12:34 +03:00
252292451f
This gives us the ability to define and use implementations locally, in where clauses/local let bindings, as well as flag local definitions as hints. It's not yet quite equivalent to global hints, however, since it translated the hint to a local let binding, which doesn't reduce, so if something relies on the reduction behaviour of the hint, it won't work. This refinement is coming later
49 lines
961 B
Idris
49 lines
961 B
Idris
data Foo : Type where [noHints]
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A : Foo
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B : Foo
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findA : {auto foo : Foo} -> String
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findA {foo = A} = "Found an A"
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findA {foo = _} = "Failed to find an A"
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Baz : String -> Type
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Baz s = s = "Found an A"
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baz : (s : String ** Baz s)
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baz = let %hint arg : Foo
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arg = A
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in (findA ** Refl)
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interface Gnu where
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constructor MkGnu
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hasFoo : Foo
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findB : Gnu => String
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findB = case hasFoo of
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B => "Found a B"
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_ => "Failed to find a B"
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Bar : String -> Type
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Bar s = s = "Found a B"
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bar : (s : String ** Bar s)
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bar = let %hint arg : Gnu
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arg = MkGnu B
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in (findB ** Refl)
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interface Gnat a where
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constructor MkGnat
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makeFoo : a -> Foo
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record More where
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constructor MkMore
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0 Ty : Type
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%unbound_implicits off
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bug : forall a . a -> (s : String ** Bar s)
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bug {a} x = let M : More
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M = MkMore a
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%hint arg : Gnat (Ty M)
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arg = MkGnat (const B)
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in (findB ** Refl)
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