PropCheck.when_fail

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when_fail(prop, action)

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Execute an action, if the property fails.

The action field should contain an expression or statement block that produces some side-effect (e.g. prints something to the screen). In case this test fails, action will be executed. Note that the output of such actions is not affected by the verbosity setting of the main application.

iex> use PropCheck
iex> quickcheck(
...>   when_fail(false, IO.puts "when_fail: Property failed")
...>)
false