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1. onpagehide :: AttributeValue -> Attribute

   blaze-html	Text.Blaze.XHtml5.Attributes

   Combinator for the onpagehide attribute. Example:

   div ! onpagehide "bar" $ "Hello."
   

   Result:

   <div onpagehide="bar">Hello.</div>
   

2. width :: AttributeValue -> Attribute

   blaze-html	Text.Blaze.XHtml5.Attributes

   Combinator for the width attribute. Example:

   div ! width "bar" $ "Hello."
   

   Result:

   <div width="bar">Hello.</div>
   

3. package genvalidity

   Testing utilities for the validity library Note: There are companion instance packages for this library:

   • genvalidity-aeson
   • genvalidity-bytestring
   • genvalidity-containers
   • genvalidity-path
   • genvalidity-scientific
   • genvalidity-text
   • genvalidity-time
   • genvalidity-unordered-containers
   • genvalidity-uuid
   • genvalidity-vector

4. module Data.GenValidity

   GenValid exists to make tests involving Validity types easier and speed up the generation of data for them. To implement tests for this datatype, we would have to be able to generate both primes. We could do this with a generator like this one:

   (Prime <$> 'arbitrary') `suchThat` isValid
   

   However, this is tedious and inefficient, as well as quite naive (because arbitrary tends to use very naive generators). The GenValid type class allows you to specify how to (efficiently) generate valid data of the given type to allow for easier and quicker testing. The default implementation of GenValid already gives you a generator and shrinking function for free:

   instance GenValid Prime
   

   For example, to generate primes, we don't have to consider even numbers other than 2. A more efficient implementation could then look as follows:

   instance GenValid Prime where
   genValid = Prime <$>
   (oneof
   [ pure 2
   , ((\y -> 2 * abs y + 1) <$> arbitrary) `suchThat` isPrime)
   ])
   

   Typical examples of tests involving validity could look as follows:

   it "succeeds when given valid input" $ do
   forAllValid $ \input ->
   myFunction input `shouldSatisfy` isRight
   

   it "produces valid output when it succeeds" $ do
   forAllValid $ \input ->
   case myFunction input of
   Nothing -> return () -- Can happen
   Just output -> output `shouldSatisfy` isValid
   

   Definitely also look at the companion packages for more info on how to use this package.

5. class GGenValid (f :: Type -> Type)

   genvalidity	Data.GenValidity

   No documentation available.

6. class GValidRecursivelyShrink (f :: Type -> Type)

   genvalidity	Data.GenValidity

   No documentation available.

7. class GValidSubterms (f :: Type -> Type) a

   genvalidity	Data.GenValidity

   No documentation available.

8. class GValidSubtermsIncl (f :: Type -> Type) a

   genvalidity	Data.GenValidity

   No documentation available.

9. class Validity a => GenValid a

   genvalidity	Data.GenValidity

   A class of types for which valid values can be generated to be valid.

   How to instantiate GenValid

   Step 1: Try to instantiate GenValid without overriding any functions. It is possible that, if few values are valid or if validity checking is expensive, the resulting generator is too slow. In that case, go to Step 2. Step 2: Consider using genValidStructurallyWithoutExtraChecking and shrinkValidStructurallyWithoutExtraFiltering to speed up generation. This only works if your type has a derived or trivial Validity instance. Step 3: If that still is not fast enough, consider writing your own generator and shrinking function. Make sure to generate any possible valid value, but only valid values.

   A note about Arbitrary

   If you also write Arbitrary instances for GenValid types, it may be best to simply use

   instance Arbitrary A where
   arbitrary = genValid
   shrink = shrinkValid
   

10. gGenValid :: GGenValid f => Gen (f a)

    genvalidity	Data.GenValidity

    No documentation available.

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