append -- r7rs Definition

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Kind

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procedure;

Implemented by

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• append (from vonuvoli);

Procedure signature

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Procedure variants:

• (() -> (null))
  • inputs: none;
  • output: a value of type null;
• (((a any)) -> ((a any)))
  • input: a of type any;
  • output: a of type any;
• ((list-proper |2...|) -> (list-proper))
  • inputs:
    • a value of type list-proper;
    • ... -- at least 2 times;
  • output: a value of type list-proper;
• ((&variadic-min +1 list-proper &trailing any) -> (list-dotted))
  • inputs:
    • (variadic) a value of type list-proper;
    • (variadic -- at least one time;)
    • (trailing) a value of type any;
  • output: a value of type list-dotted;

Exports

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• scheme:base -- (scheme base);

Exports recursive

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• scheme -- (scheme);

Description

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(append list ...)

Domain: The last argument, if there is one, can be of any type.

Returns a list consisting of the elements of the first list followed by the elements of the other lists. If there are no arguments, the empty list is returned. If there is exactly one argument, it is returned. Otherwise the resulting list is always newly allocated, except that it shares structure with the last argument. An improper list results if the last argument is not a proper list.

(append '(x) '(y))              ===>  (x y)
(append '(a) '(b c d))          ===>  (a b c d)
(append '(a (b)) '((c)))        ===>  (a (b) (c))

(append '(a b) '(c . d))        ===>  (a b c . d)
(append '() 'a)                 ===>  a

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The text herein was sourced and adapted as described in the "R7RS attribution of various text snippets" appendix.

Referenced-types

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• null;
• any;
• list-proper;
• list-dotted;