1. kimagure

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    kimagure
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@@ -6,14 +6,12 @@
data V err result
```
The Validation package gives us a nice way to validate values using applicative validation. From the docs:
-```
-Applicative validation differs from monadic validation using Either in that it allows us to collect
+> Applicative validation differs from monadic validation using Either in that it allows us to collect
multiple errors using a Semigroup, whereas Either terminates on the first error.
-```
In other words, modeling validations with Either would fall out on the first error. We can collect one or more errors in this case using a structure that is an instance of Semigroup.
Note that this does not work with a Monoid. Using a Monoid would not make sense in that it would provide an identity that cannot reasonably be used -- there is no case in which you would have an empty list of errors and fall on the error case of the validation.