Validating number in perl
ok(sub , 5, '2 and 2 is 4'); # this test fails for the obvious mathematical # reason and prints a descriptive error.will return the same nodes as the previous example, and bring all of the "bar" elements' descendants along for the ride.function which returns true (1) only if the entire expression we pass to it evaluates to true.We need only check that the number of "item" elements is equal to the number of "item" elements that have the child elements we are testing for.Next we need to confirm that our order document contains a "customer" element, and that the "customer" element contains a "shipping_info" element.Rather than running separate tests for each, we can combine these tests into a single expression and, if either element is missing or misplaced, our test will fail.The handful of tests that we currently have clearly would not be sufficient validation for a production environment, but with these few examples, you hopefully have a clear view of the basics and could extend the test script to handle nearly any case.You could, for example, iterate over the "quantity" elements and test each As much as I would love to take credit for basic ideas presented here, I admit that the notion of using XPath expressions to validate an XML document's structure is not at all new.
An an example, consider the following two tests: ok('good','good', 'its all good'); # this test passes because the first two # arguments return the same values.
Type:: Tiny is a zero-dependency implementation of type constraints that can be used with Moose, Mouse and Moo alike.
(No more need to build separate type libraries for each of them! It's validation we'll look at today; specifically validating sub parameters.
In fact, this concept is the foundation of Rick Jelliffe's popular Schematron.
Thanks should also go to Matt Sergeant, the author of Ax Kit, for pointing out that Perl's modules would make a nifty environment for a Perl Schematronesque clone.