ext/tags.go
func (tag ipv4Tag) SetString(span opentracing.Span, value string) {
	span.SetTag(string(tag), value)
}
func (tag ipv4Tag) SetString(span opentracing.Span, value string) {
	span.SetTag(string(tag), value)
}
func ( tag ipv4Tag ) SetString ( span opentracing . Span , value string ) { span . SetTag ( string ( tag ) , value ) }
// SetString records IP v4 host address of the peer as a .-separated tuple to the `span`. E.g., "127.0.0.1"
SetString records IP v4 host address of the peer as a . - separated tuple to the span . E . g . 127 . 0 . 0 . 1