billboswell
Effective Haskell: Chapter 9 - Monad instance error (page 357)
Creating the instance of Monad Outlaw described in the text results in error:
• No instance for (Applicative Outlaw)
arising from the superclasses of an instance declaration
• In the instance declaration for ‘Monad Outlaw’
Resolved by adding Applicative instance:
Instance Applicative Outlaw where
pure = return
First Post!
RebeccaSkinner
Author of Effective Haskell
Good catch, thanks. I’ll add an errata item about this.
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