template.go
func (t *Template) Execute(w io.Writer, m map[string]interface{}) (int64, error) {
	return t.ExecuteFunc(w, func(w io.Writer, tag string) (int, error) { return stdTagFunc(w, tag, m) })
}
func (t *Template) Execute(w io.Writer, m map[string]interface{}) (int64, error) {
	return t.ExecuteFunc(w, func(w io.Writer, tag string) (int, error) { return stdTagFunc(w, tag, m) })
}
// Execute substitutes template tags (placeholders) with the corresponding
// values from the map m and writes the result to the given writer w.
//
// Substitution map m may contain values with the following types:
//   * []byte - the fastest value type
//   * string - convenient value type
//   * TagFunc - flexible value type
//
// Returns the number of bytes written to w.