namespace

type Namespace interface {
	// Add tries to create a mapping from ID to name. If name
	// is used by other ID, then a renamed one will be returned.
	Add(name, id string) (result string)

	// Get returns the Added name of id. If none found, the result will
	// be an empty string.
	Get(id string) (name string)

	// ID is the reverse operation of Get. It returns the ID that maps
	// to the given name.
	ID(name string) (id string)

	// Reserve tries to create a mapping from ID to name without any
	// renaming. The result indicates whether it succeeds.
	Reserve(name, id string) (ok bool)

	// MustReserve tries to create a mapping from ID to name without any
	// renaming. If the name is occupied, this function will panic.
	MustReserve(name, id string)

	// Iterate passes each key and value in the namespace to f.
	// If f returns false, Iterate stops the iteration.
	Iterate(v func(name, id string) (shouldContinue bool))
}