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(elisp)Vector Functions

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Functions for Vectors
=====================

   Here are some functions that relate to vectors:

 - Function: vectorp object
     This function returns `t' if OBJECT is a vector.

          (vectorp [a])
               => t
          (vectorp "asdf")
               => nil

 - Function: vector &rest objects
     This function creates and returns a vector whose elements are the
     arguments, OBJECTS.

          (vector 'foo 23 [bar baz] "rats")
               => [foo 23 [bar baz] "rats"]
          (vector)
               => []

 - Function: make-vector length object
     This function returns a new vector consisting of LENGTH elements,
     each initialized to OBJECT.

          (setq sleepy (make-vector 9 'Z))
               => [Z Z Z Z Z Z Z Z Z]

 - Function: vconcat &rest sequences
     This function returns a new vector containing all the elements of
     the SEQUENCES.  The arguments SEQUENCES may be any kind of arrays,
     including lists, vectors, or strings.  If no SEQUENCES are given,
     an empty vector is returned.

     The value is a newly constructed vector that is not `eq' to any
     existing vector.

          (setq a (vconcat '(A B C) '(D E F)))
               => [A B C D E F]
          (eq a (vconcat a))
               => nil
          (vconcat)
               => []
          (vconcat [A B C] "aa" '(foo (6 7)))
               => [A B C 97 97 foo (6 7)]

     The `vconcat' function also allows byte-code function objects as
     arguments.  This is a special feature to make it easy to access
     the entire contents of a byte-code function object.  Note:
     Byte-Code Objects.

     The `vconcat' function also allows integers as arguments.  It
     converts them to strings of digits, making up the decimal print
     representation of the integer, and then uses the strings instead
     of the original integers.  *Don't use this feature; we plan to
     eliminate it.  If you already use this feature, change your
     programs now!*  The proper way to convert an integer to a decimal
     number in this way is with `format' (Note: Formatting Strings)
     or `number-to-string' (Note: String Conversion).

     For other concatenation functions, see `mapconcat' in Note:
     Mapping Functions, `concat' in Note: Creating Strings, and
     `append' in Note: Building Lists.

   The `append' function provides a way to convert a vector into a list
with the same elements (Note: Building Lists):

     (setq avector [1 two (quote (three)) "four" [five]])
          => [1 two (quote (three)) "four" [five]]
     (append avector nil)
          => (1 two (quote (three)) "four" [five])