format.go
func (f *defaultFormats) DelByName(name string) bool {
	f.Lock()
	defer f.Unlock()

	nme := f.normalizeName(name)

	for i, v := range f.data {
		if v.Name == nme {
			f.data[i] = knownFormat{} // release
			f.data = append(f.data[:i], f.data[i+1:]...)
			return true
		}
	}
	return false
}
func (f *defaultFormats) DelByName(name string) bool {
	f.Lock()
	defer f.Unlock()

	nme := f.normalizeName(name)

	for i, v := range f.data {
		if v.Name == nme {
			f.data[i] = knownFormat{} // release
			f.data = append(f.data[:i], f.data[i+1:]...)
			return true
		}
	}
	return false
}
// DelByName removes the format by the specified name, returns true when an item was actually removed