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| From | Paul Rubin <no.email@nospam.invalid> |
| Newsgroups | comp.lang.haskell |
| Subject | Re: Nested "Maybe" |
| Date | Fri, 09 Apr 2021 14:27:12 -0700 |
| Organization | A noiseless patient Spider |
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Paul Rubin <no.email@nospam.invalid> writes: > data Precision a = Roughly a | Exactly a > data Approximate a = Maybe (Precision a) Alternatively maybe you want an actual 3-way Maybe, e.g. data Approximate a = Invalid | Roughly a | Exactly a and then you could write typeclass instances (monad, monoid, etc.) analogously with Maybe.
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Nested "Maybe" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-04-09 22:13 +0100
Re: Nested "Maybe" Paul Rubin <no.email@nospam.invalid> - 2021-04-09 14:24 -0700
Re: Nested "Maybe" Paul Rubin <no.email@nospam.invalid> - 2021-04-09 14:27 -0700
Re: Nested "Maybe" Mark Carroll <mtbc@bcs.org> - 2021-04-09 17:33 -0400
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