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Version: 1.0
For the complete Mojo documentation index, see llms.txt. Markdown versions of all pages are available by appending .md to any URL (e.g. /docs/manual/basics.md).

Defaultable

The Defaultable trait describes a type with a default constructor.

Implementing the Defaultable trait requires the type to define an __init__ method with no arguments:

struct Foo(Defaultable):
    var s: String

    def __init__(out self):
        self.s = "default"

You can now construct a generic Defaultable type:

def default_init[T: Defaultable]() -> T:
    return T()

var foo = default_init[Foo]()
print(foo.s)
default

Implemented traits​

AnyType

Required methods​

__init__​

__init__(out self: _Self)

Create a default instance of the value.

Returns:

_Self

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