Using reflect, how do you set the value of a struct field?

having a rough time working with struct fields using reflect package. in particular, have not figured out how to set the field value.

type t struct { fi int; fs string } var r t = t{ 123, “jblow” } var i64 int64 = 456

  1. getting Name of field i - this seems to work var field = reflect.TypeOf(r).Field(i).Name
  2. getting value of field i as a) interface{}, b) int - this seems to work var iface interface{} = reflect.ValueOf(r).Field(i).Interface() var i int = int(reflect.ValueOf(r).Field(i).Int())
  3. setting value of field i - try one - panic reflect.ValueOf(r).Field(i).SetInt( i64 ) panic : reflect.Value·SetInt using value obtained using unexported fieldassuming it did not like field names “id” and “name”, so renamed to “Id” and "Name"a) is this assumption correct?b) if correct, thought not necessary since in same file / package
  4. setting value of field i - try two (with field names capitalized ) - panic reflect.ValueOf(r).Field(i).SetInt( 465 ) reflect.ValueOf(r).Field(i).SetInt( i64 ) panic : reflect.Value·SetInt using unaddressable value

Instructions below by @peterSO are thorough and high quality

Four. this works:

reflect.ValueOf(&r).Elem().Field(i).SetInt( i64 )

he documents as well that the field names must be exportable (begin with capital letter)