func (m *Message) SetBodyWriter(contentType string, f func(io.Writer) error, settings ...PartSetting) {
	m.parts = []*part{m.newPart(contentType, f, settings)}
}
func (m *Message) SetBodyWriter(contentType string, f func(io.Writer) error, settings ...PartSetting) {
	m.parts = []*part{m.newPart(contentType, f, settings)}
}
func ( m * Message ) SetBodyWriter ( contentType string , f func ( io . Writer ) error , settings ... PartSetting ) { m . parts = [ ] * part { m . newPart ( contentType , f , settings ) } }
// SetBodyWriter sets the body of the message. It can be useful with the
// text/template or html/template packages.
SetBodyWriter sets the body of the message . It can be useful with the text / template or html / template packages .