Data update

Task/Classes/Julia/classes.jl

@@ -0,0 +1,20 @@
+abstract type Mammal end
+habitat(::Mammal) = "planet Earth"
+
+struct Whale <: Mammal
+    mass::Float64
+    habitat::String
+end
+Base.show(io::IO, ::Whale) = print(io, "a whale")
+habitat(w::Whale) = w.habitat
+
+struct Wolf <: Mammal
+    mass::Float64
+end
+Base.show(io::IO, ::Wolf) = print(io, "a wolf")
+
+arr = [Whale(1000, "ocean"), Wolf(50)]
+println("Type of $arr is ", typeof(arr))
+for a in arr
+    println("Habitat of $a: ", habitat(a))
+end