The zero package

[Tags:bsd3, library]

Monoid is a Semigroup glued with a neutral element called mempty. In the same idea, Zero is a Semigroup glued with an absorbing element called zero.

Keep in mind that Zero requires Semigroup. If you have Semigroup defined to work with Monoid, you might end up with no way to implement Zero. That’s why the Semigroup instance for Maybe is confusing, because it relies on Monoid, and cannot be used with Zero. Success is the Zero equivalent of Maybe + Monoid.


Versions 0.1, 0.1.1, 0.1.2, 0.1.3,, 0.1.4
Change log
Dependencies base (>=4.8 && <5.0), semigroups (>=0.16 && <0.19) [details]
License BSD3
Copyright Dimitri Sabadie
Author Dimitri Sabadie <>
Maintainer Dimitri Sabadie <>
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Source repository head: git clone
Uploaded Wed May 25 11:27:26 UTC 2016 by DimitriSabadie
Distributions LTSHaskell:0.1.4, NixOS:0.1.4, Stackage:0.1.4, Tumbleweed:0.1.4
Downloads 477 total (7 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2016-05-25 [all 1 reports]




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