Thanks for sharing your TIMTOWTDIness :)

Taking it seriously it demonstrate an important concept: learning is a path to follow, possibly alongside a teacher. Many of us can produce ten different ways to satisfy an assignment using perl. But this is not the point.

As you noticed (lack of lower case specification for the array and the costraint of a single quote for the dash) it is very important to be clear in the assignement, making it also pedantic, and to be sure it imply the usage of already presented elements.

A teacher must introduce concepts and verify how much students have incorporated them.

Teaching, at first, is dedicated to fill ignorant's gap with notions and concepts (then teach how to learn and how to think, but is not my goal).

So a course (in general but also mines) starts with assumed ignorance in one field, and step by step introduces elements and tests the overall students understanding.

To produce PPI tests making all your example to be verified is an immane task, not worth even to plan. While teaching or learning the appropriate virtue is patience not hubris infact to learn is fondamental to recognize somethig superior who teach you.

So I can add this note to my Perl::Teacher project:

about assignements:

-be sure to imply only already introduced elements, possibly refering 
+to the lesson where they were discussed
-in the hints section put reminders to previous lessons
-be pedantic in the assignement
-possibly show up what was expected by tests when datastructures are i
+nvolved (this can clarify an assignement)
[download]

Tux!! out of the classroom!! :)

L*