43 lines
791 B
Text
43 lines
791 B
Text
{-|
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Any function `f` that is a `Monoid` must satisfy the following law:
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```
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t : Type
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f : ./Monoid t
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xs : List (List t)
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f (./List/concat t xs) = f (./map (List t) t f xs)
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```
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Examples:
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```
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./Bool/and
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: ./Monoid Bool
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./Bool/or
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: ./Monoid Bool
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./Bool/even
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: ./Monoid Bool
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./Bool/odd
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: ./Monoid Bool
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./List/concat
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: ∀(a : Type) → ./Monoid (List a)
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./List/shifted
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: ∀(a : Type) → ./Monoid (List { index : Natural, value : a })
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./Natural/sum
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: ./Monoid Natural
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./Natural/product
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: ./Monoid Natural
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./Optional/head
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: ∀(a : Type) → ./Monoid (Optional a)
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./Optional/last
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: ∀(a : Type) → ./Monoid (Optional a)
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./Text/concat
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: ./Monoid Text
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```
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-}
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let Monoid
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: ∀(m : Type) → Type
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= λ(m : Type) → List m → m
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in Monoid
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