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Package ring
Overview ▹
Overview ▾
Package ring implements operations on circular lists.
Index ▹
type Ring
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.
type Ring struct {
Value interface{} // for use by client; untouched by this library
// contains filtered or unexported fields
}
func New
func New(n int) *Ring
New creates a ring of n elements.
func (*Ring) Do
func (r *Ring) Do(f func(interface{}))
Do calls function f on each element of the ring, in forward order. The behavior of Do is undefined if f changes *r.
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func (*Ring) Len
func (r *Ring) Len() int
Len computes the number of elements in ring r. It executes in time proportional to the number of elements.
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func (*Ring) Link
func (r *Ring) Link(s *Ring) *Ring
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.
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func (*Ring) Move
func (r *Ring) Move(n int) *Ring
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.
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func (*Ring) Next
func (r *Ring) Next() *Ring
Next returns the next ring element. r must not be empty.
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func (*Ring) Prev
func (r *Ring) Prev() *Ring
Prev returns the previous ring element. r must not be empty.
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func (*Ring) Unlink
func (r *Ring) Unlink(n int) *Ring
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.
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