arrays - golang prepend a string to a slice ...interface{}

Question

I've a method that has as an argument v ...interface{}, I need to prepend this slice with a string. Here is the method:

func (l Log) Error(v ...interface{}) {
  l.Out.Println(append([]string{" ERROR "}, v...))
}

When I try with append() it doesn't work:

> append("some string", v)
first argument to append must be slice; have untyped string
> append([]string{"some string"}, v)
cannot use v (type []interface {}) as type string in append

What's the proper way to prepend in this case?

Answer 1

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