Property-Based Testing with PropEr, Erlang, and Elixir

Custom Generators

Question 1

• collect(Term, BoolExpression) (in Elixir, BoolExpression |> collect(Term))
• aggregate([Term], BoolExpression) (in Elixir, BoolExpression |> aggregate(Term))

Question.

Question 2

?LET(Var, Generator, ErlangExpr); otherwise, the generators are abstract representations that won’t be modifiable the way the generated data would be. The same syntax in Elixir is let var <- Generator do ElixirExpr end instead.

Question.

Question 3

Whenever a generator that may probabilistically choose multiple branches is called, using eager evaluation means that all alternative paths for it will be evaluated at once. If the generator is made recursive, this can quickly blow the size of the computation to very large levels. The ?LAZY(Generator) ...