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7.2 Construction of Lists

— procedure: list object ...

Returns a list of its arguments.

          (list 'a (+ 3 4) 'c)                    => (a 7 c)
          (list)                                  => ()
     

These expressions are equivalent:

          (list obj1 obj2 ... objN)
          (cons obj1 (cons obj2 ... (cons objN '()) ...))
     
— procedure: make-list k [element]

(SRFI 1) This procedure returns a newly allocated list of length k, whose elements are all element. If element is not supplied, it defaults to the empty list.

          (make-list 4 'c)                        => (c c c c)
     
— procedure: cons* object object ...

(SRFI 1) cons* is similar to list, except that cons* conses together the last two arguments rather than consing the last argument with the empty list. If the last argument is not a list the result is an improper list. If the last argument is a list, the result is a list consisting of the initial arguments and all of the items in the final argument. If there is only one argument, the result is the argument.

          (cons* 'a 'b 'c)                        => (a b . c)
          (cons* 'a 'b '(c d))                    => (a b c d)
          (cons* 'a)                              => a
     

These expressions are equivalent:

          (cons* obj1 obj2 ... objN-1 objN)
          (cons obj1 (cons obj2 ... (cons objN-1 objN) ...))
     
— procedure: list-tabulate k init-proc
— procedure: make-initialized-list k init-proc

Returns a k-element list. Element i of the list, where 0 <= i < k, is produced by (init-proc i). No guarantee is made about the dynamic order in which init-proc is applied to these indices.

          (list-tabulate 4 values) => (0 1 2 3)
     

list-tabulate is defined by SRFI 1.

— procedure: list-copy list

(SRFI 1) Returns a newly allocated copy of list. This copies each of the pairs comprising list. This could have been defined by

          (define (list-copy list)
            (if (null? list)
                '()
                (cons (car list)
                      (list-copy (cdr list)))))
     
— procedure: iota count [start [step]]

(SRFI 1) Returns a list containing the elements

          (start start+step ... start+(count-1)*step)
     

Count must be an exact non-negative integer, while start and step can be any numbers. The start and step parameters default to 0 and 1, respectively.

          (iota 5) => (0 1 2 3 4)
          (iota 5 0 -0.1) => (0 -0.1 -0.2 -0.3 -0.4)
     
— procedure: vector->list vector
— procedure: subvector->list vector start end

vector->list returns a newly allocated list of the elements of vector.
subvector->list returns a newly allocated list of the elements of the given subvector. The inverse of vector->list is list->vector.

          (vector->list '#(dah dah didah))        => (dah dah didah)
     
— procedure: string->list string
— procedure: substring->list string start end

string->list returns a newly allocated list of the character elements of string.
substring->list returns a newly allocated list of the character elements of the given substring. The inverse of string->list is list->string.

          (string->list "abcd")                   => (#\a #\b #\c #\d)
          (substring->list "abcdef" 1 3)          => (#\b #\c)