ring

Documentation

Overview

Package ring implements operations on circular lists.

Index

• type Ring
  • func New[V any](n int) *Ring[V]
  • func (r *Ring[V]) Do(f func(any))
  • func (r *Ring[V]) Len() int
  • func (r *Ring[V]) Link(s *Ring[V]) *Ring[V]
  • func (r *Ring[V]) Move(n int) *Ring[V]
  • func (r *Ring[V]) Next() *Ring[V]
  • func (r *Ring[V]) Prev() *Ring[V]
  • func (r *Ring[V]) Unlink(n int) *Ring[V]

Types

type Ring

type Ring[V any] struct {
	Value V // for use by client; untouched by this library
	// contains filtered or unexported fields
}

A Ring is an element of a circular list, or ring. Rings do not have a beginning or end; a pointer to any ring element serves as reference to the entire ring. Empty rings are represented as nil Ring pointers. The zero value for a Ring is a one-element ring with a nil Value.

func New

func New[V any](n int) *Ring[V]

New creates a ring of n elements.

func (*Ring[V]) Do

func (r *Ring[V]) Do(f func(any))

Do calls function f on each element of the ring, in forward order. The behavior of Do is undefined if f changes *r.

func (*Ring[V]) Len

func (r *Ring[V]) Len() int

Len computes the number of elements in ring r. It executes in time proportional to the number of elements.

func (*Ring[V]) Link

func (r *Ring[V]) Link(s *Ring[V]) *Ring[V]

Link connects ring r with ring s such that r.Next() becomes s and returns the original value for r.Next(). r must not be empty.

If r and s point to the same ring, linking them removes the elements between r and s from the ring. The removed elements form a subring and the result is a reference to that subring (if no elements were removed, the result is still the original value for r.Next(), and not nil).

If r and s point to different rings, linking them creates a single ring with the elements of s inserted after r. The result points to the element following the last element of s after insertion.

func (*Ring[V]) Move

func (r *Ring[V]) Move(n int) *Ring[V]

Move moves n % r.Len() elements backward (n < 0) or forward (n >= 0) in the ring and returns that ring element. r must not be empty.

func (*Ring[V]) Next

func (r *Ring[V]) Next() *Ring[V]

Next returns the next ring element. r must not be empty.

func (*Ring[V]) Prev

func (r *Ring[V]) Prev() *Ring[V]

Prev returns the previous ring element. r must not be empty.

func (*Ring[V]) Unlink

func (r *Ring[V]) Unlink(n int) *Ring[V]

Unlink removes n % r.Len() elements from the ring r, starting at r.Next(). If n % r.Len() == 0, r remains unchanged. The result is the removed subring. r must not be empty.