[Function]

(next pattern [length])

Returns one or more elements from pattern according to length. If length is unspecified or false then just the next element from pattern is returned. If length is a number then that many elements are read from the pattern and returned in a list. Otherwise if length is true then the next period's worth data is read from the pattern.

(define p (new cycle :of '(a b c d) ))

(next p)
⇒ a

(next p)
⇒ b

(next p 6)
⇒ (c d a b c d)

(next p #t)
⇒ (a b c d)

See Also:

• eod? [Function]
• eop? [Function]
• map-pattern-data [Function]
• pattern-state [Function]
• pattern-value [Function]
• pattern? [Function]