def assit_block(&block)
      errors = []
      assit((block.call(errors) && errors.size == 0), errors.join(', '))
    end
def assit_block(&block)
      errors = []
      assit((block.call(errors) && errors.size == 0), errors.join(', '))
    end
Executes the given block and asserts if the result is true. This allows
 you to assert on complex, custom expressions and be able to disable
 those expressions together with the assertions. See the README for more.

 The block will be passed a single array, to which error messages can be
 append. The assertion will always fail if an error is appended to the
 array.