Improvements to HW1a (Pokémon)

[gdalle]

• Invite students to use the documentation (? in the REPL / docs tab in Pluto)
• Present intro tutorial before the homework
• Say that just because checks are passing doesn't mean the answer is correct
• Add question numbers
• Explain what an empty struct means + how to compare mutable and immutable structs (== vs ===)
• Clarify inner / outer constructors
• Note on matrix indexing to prevent them from using linear indices
• Give a reference for various kinds of type dispatch syntax (f(x::X) vs f(x::Y) where {Y<:X})
• Specify expected output for attack(::Corgi, ::Pokemon), and state that we do not accept catch-all methods (code should rely on dispatch instead)
• Define what we mean by method ambiguity and explicitly lead students to find and resolve it
• Fix check_defense_philip check
• Explain how boundaries should be handled in the step! function
• Make it clear that the attacker cannot attack itself

[alanedelman]

We must have a yamper

as well as a philip