How to Initialize Nested Struct Fields in Go Using Field References?

Nested Struct Initialization with Field References

The task is to initialize a nested struct with literal values while setting a field belonging to a parent struct. Here's an example:

type A struct {
    MemberA string
}

type B struct {
    A
    MemberB string
}

Attempts to initialize MemberA directly in a struct literal, as shown below, will fail:

b := B {
    MemberA: "test1",
    MemberB: "test2",
}
fmt.Printf("%+v\n", b)

This results in the error: "unknown B field 'MemberA' in struct literal."

To initialize MemberA correctly, you must provide a valid instance of the parent struct, A, as seen in this code:

b := B {
    A: A{MemberA: "test1"}, // Initialize the parent struct instance
    MemberB: "test2",
}

The compiler error message "unknown B field 'MemberA' in struct literal" indicates that MemberA is not a known field of B directly. Instead, it belongs to the embedded A type. When initializing the B struct, the anonymous A instance is only known under the type name A, and its members are not visible outside the instance until it is created.

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