Structs in Julia

Based on the provided instructions and the given input with a target language of Julia, here is the extracted Go code translated to Julia with an appropriate explanation in Markdown format suitable for Hugo:

Go’s structs are typed collections of fields. They’re useful for grouping data together to form records.

Example in Julia#

This Person mutable struct type has name and age fields.

mutable struct Person
    name::String
    age::Int
end

new_person constructs a new Person struct with the given name.

function new_person(name::String)::Person
    p = Person(name, 42)
    return p
end

This syntax creates a new struct.

println(Person("Bob", 20))

You can name the fields when initializing a struct.

println(Person(name="Alice", age=30))

Omitted fields will be zero-valued.

println(Person(name="Fred", age=0))

An & prefix yields a pointer to the struct (in Julia, we simply use the struct).

println(Person(name="Ann", age=40))

It’s idiomatic to encapsulate new struct creation in constructor functions.

println(new_person("Jon"))

Access struct fields with a dot.

s = Person("Sean", 50)
println(s.name)

You can also use dots with struct references - Julia automatically handles the reference.

sp = s
println(sp.age)

Structs are mutable.

sp.age = 51
println(sp.age)

If a struct type is only used for a single value, we don’t have to give it a name. The value can have an anonymous struct type. This technique is commonly used for table-driven tests.

dog = (; name = "Rex", isGood = true)
println(dog)

Running the Code#

To run the Julia code, you can simply execute the script using the julia command.

$ julia structs.jl

The expected output of running the code would be:

Person("Bob", 20)
Person("Alice", 30)
Person("Fred", 0)
Person("Ann", 40)
Person("Jon", 42)
Sean
50
51
(name = "Rex", isGood = true)

Now that we can run and build basic Julia programs, let’s learn more about the language.

Next example: Methods.