b69010d05c
I think is better to continue use safe ```Map.fetch``` until we familiarize users with dangerous function concept. Not every body comes from ruby background, with knowledge of ```?``` and ```!``` function notations. test ifx
47 lines
1.0 KiB
Elixir
47 lines
1.0 KiB
Elixir
defmodule Structs do
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use Koans
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defmodule Person do
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defstruct [:name, :age]
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end
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koan "Structs are defined and named after a module" do
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person = %Person{}
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assert person == ___
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end
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koan "Unless previously defined, fields begin as nil" do
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nobody = %Person{}
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assert nobody.age == ___
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end
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koan "You can pass initial values to structs" do
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joe = %Person{name: "Joe", age: 23}
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assert joe.name == ___
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end
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koan "Update fields with the cons '|' operator" do
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joe = %Person{name: "Joe", age: 23}
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older = %{joe | age: joe.age + 10}
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assert older.age == ___
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end
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defmodule Plane do
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defstruct passengers: 0, maker: :boeing
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end
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def plane?(%Plane{}), do: true
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def plane?(_), do: false
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koan "Or onto the type of the struct itself" do
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assert plane?(%Plane{passengers: 417, maker: :boeing}) == ___
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assert plane?(%Person{}) == ___
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end
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koan "Struct can be treated like maps" do
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silvia = %Person{age: 22, name: "Silvia"}
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assert Map.fetch(silvia, :age) == ___
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end
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end
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