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GHC 9.10.3 · lts/ghc-9.10.x · c74966e · 2026-09-27

ModuleQuickCheck-2.15.0.1Haskell2010

Test.QuickCheck.All

Note: the contents of this module are re-exported by Test.QuickCheck. You do not need to import it directly.

Test all properties in the current module, using Template Haskell. You need to have a {-# LANGUAGE TemplateHaskell #-} pragma in your module for any of these to work.

  • 7 values

Testing all properties in a module

4 declarations
valuequickCheckAll :: Q Exp
#

Test all properties in the current module. The name of the property must begin with prop_. Polymorphic properties will be defaulted to Integer. Returns True if all tests succeeded, False otherwise.

To use quickCheckAll, add a definition to your module along the lines of

return []
runTests = $quickCheckAll

and then execute runTests.

Note: the bizarre return [] in the example above is needed on GHC 7.8 and later; without it, quickCheckAll will not be able to find any of the properties. For the curious, the return [] is a Template Haskell splice that makes GHC insert the empty list of declarations at that point in the program; GHC typechecks everything before the return [] before it starts on the rest of the module, which means that the later call to quickCheckAll can see everything that was defined before the return []. Yikes!

Testing polymorphic properties

3 declarations
valuepolyQuickCheck :: Name -> ExpQ
#

Test a polymorphic property, defaulting all type variables to Integer.

Invoke as $(polyQuickCheck 'prop), where prop is a property. Note that just evaluating quickCheck prop in GHCi will seem to work, but will silently default all type variables to ()!

$(polyQuickCheck 'prop) means the same as quickCheck $(monomorphic 'prop). If you want to supply custom arguments to polyQuickCheck, you will have to combine quickCheckWith and monomorphic yourself.

If you want to use polyQuickCheck in the same file where you defined the property, the same scoping problems pop up as in quickCheckAll: see the note there about return [].