Appendix

f = e	function or constant definition of f as e
x : A	declaration that x is of type A
lambda (x : A) --> e	lambda definition for λ (x : A) . e, where x is of type A
t := e	assignment of parameter t to have value e
if b then e₁ else e₂	expression if b is true, then e₁, else e₂
match x case pᵢ ==> eᵢ	pattern matching from pᵢ to eᵢ for 1 ≤ i ≤ n
class B extends A₁ … Aₙ	class B extends classes A₁ … Aₙ
A₁ subtype A₂	A₁ extends A₂
A₁ supertype A₂	A₁ is extended by A₂
abstract f₁ … fₙ	block of functions or constants fᵢ to be defined
this	reference to itself as an instance
end	end of class definition
package	package declaration for this piece of code
import p	block of import declarations