How to Use `FieldByName` with Pointer Values in Go Reflection?

reflect: Understanding FieldByName on Pointer Values

You have defined data structures representing a person and family, where the family field is a pointer to a Family instance. However, while accessing nested fields using reflection, you encountered an error regarding calling FieldByName on a pointer Value.

The Issue Explained:

The error occurs because you're trying to call FieldByName on a pointer (reflect.Value), specifically on the family field. Reflection operations typically work on the value itself, not its pointer. When dealing with pointers, you need to dereference them first to obtain the actual value.

Solution:

To resolve this issue, you need to dereference the family pointer before accessing nested fields:

familyPtr := v.FieldByName("family")
v = reflect.Indirect(familyPtr).FieldByName("last")

1. familyPtr = v.FieldByName("family"): This line retrieves the reflect.Value for the family field, which is a pointer to the actual Family struct.
2. v = reflect.Indirect(familyPtr).FieldByName("last"): Here, we first dereference the familyPtr using Indirect to get the actual Family Value. Then, we call FieldByName("last") to access the last field within that Value.

By following this approach, you can successfully retrieve fields from within nested structures, even when the field is a pointer to another structure.

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