lappend-lazy ( list1 list2 -- result )
Lazy lists » Manipulating lazy lists

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Vocabulary
lists.lazy

Inputs

list1	a cons object
list2	a cons object

Outputs

result

a lazy list of list2 appended to list1

Word description
Perform a similar functionality to that of the append word, but in a lazy manner. No evaluation of the list elements occurs initially but a lazy-append object is returned which conforms to the list protocol. Calling car, cdr or nil? on this will evaluate elements as required. Successive calls to cdr will iterate through list1, followed by list2.

See also
leach, foldl, lmap-lazy, ltake, lfilter, lfrom, lfrom-by, lconcat, lcartesian-product, lcartesian-product*, lcartesian-map, lcartesian-map*, lmerge, lwhile, luntil

Definition

USING: kernel lists ;

IN: lists.lazy

: lappend-lazy ( list1 list2 -- result )
    over nil? [ nip ] [ <lazy-append> ] if ;