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Free Applicative Functors

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 نشر من قبل EPTCS
 تاريخ النشر 2014
  مجال البحث الهندسة المعلوماتية
والبحث باللغة English
 تأليف Paolo Capriotti




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Applicative functors are a generalisation of monads. Both allow the expression of effectful computations into an otherwise pure language, like Haskell. Applicative functors are to be preferred to monads when the structure of a computation is fixed a priori. That makes it possible to perform certain kinds of static analysis on applicative values. We define a notion of free applicative functor, prove that it satisfies the appropriate laws, and that the construction is left adjoint to a suitable forgetful functor. We show how free applicative functors can be used to implement embedded DSLs which can be statically analysed.



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