How deeply does Clojure: The Essential Reference cover cycle?

Defines inputs, outputs, laziness, empty-input behavior, and implementation strategy without detailing the Java internals.

Cycle

As explained in Clojure: The Essential Reference

cycle is a Clojure function that repeatedly traverses input items in order to produce an unbounded lazy sequence.

cycle takes a collection and lazily produces an unbounded sequence by repeating its items in their original order. Use take or another bounded consumer when only a finite prefix is needed. section 9.2 section 9.2.3

Key behavior:

Accepts a sequential collection or nil; an empty input produces an empty persistent list. section 9.2.3
Returns a sequence-compatible clojure.lang.Cycle object that repeats indefinitely. section 9.2.3
Differs from repeat: repeat duplicates one value, while cycle traverses multiple input values in order. section 9.2

Bound an infinite cycle

(take 5 (cycle [1 2 3])) ;; (1 2 3 1 2) A short collection can therefore supply a longer sequential view, such as alternating signs, recurring traffic-light states, or repeated symbols. section 9.2.3

(take 5 (repeat (+ 1 1))) ; #1
;; (2 2 2 2 2)

(take 5 (cycle [1 2 3])) ; #2
;; (1 2 3 1 2)

Compare finite observation of repeat and cycle directly through executable examples. section 9.2.3

How Clojure: The Essential Reference covers it

Cover of Clojure: The Essential Reference

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Also explained in

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The Well-Grounded Rubyist, Fourth Editioncycle is a Ruby Enumerable method that repeatedly traverses an enumerable object's elements, optionally for a specified number of cycles.

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Related concepts

infinite data structureproduces · An infinite data structure represents or generates an unbounded number of elements, commonly by producing them lazily rather than storing them all.
generatorkind of · A generator is a computational component or construct that produces data or values from inputs, representations, context, or specified constraints.
each_entryequivalent to · each_entry is a Ruby enumeration method that yields each element of a collection to a block.
zipuses · Zip is an operation that combines corresponding elements from multiple iterables or collections into paired or otherwise combined results.
concatenationalternative to · Concatenation is the operation of joining ordered sequences end to end to form a single sequence.
cycleimplements · A cycle is a recurring sequence of connected elements or events that returns to an earlier point, forming a loop.

This explainer was generated by Manning's knowledge graph from the text of Clojure: The Essential Reference. The section links point to the parts of the book it draws on.