declaration—a declare expression; not evaluated.
tag—a go tag; not evaluated.
statement—a compound form; evaluated as described below.
return-from form is executed,
the values passed from that form;
otherwise, the values returned by the result-form
nil if there is no result-form.
dotimes iterates over a series of integers.
dotimes evaluates count-form,
which should produce an integer.
If count-form is zero or negative,
the body is not executed.
dotimes then executes the body once for each integer from 0 up to
but not including
the value of count-form,
in the order in which the
tags and statements occur, with
var bound to each integer.
At the time result-form is processed, var is bound to
the number of times the body was executed.
An implicit block
return may be used to terminate the loop immediately without
performing any further iterations, returning zero or more values.
The body of the loop is an implicit tagbody;
it may contain tags to serve as the targets of
Declarations may appear before the body of the loop.
The scope of the binding of var does not include the count-form, but the result-form is included.
It is implementation-dependent whether
establishes a new binding of var on each iteration
or whether it establishes a binding for var once at the
beginning and then assigns it on any subsequent iterations.
(dotimes (temp-one 10 temp-one)) → 10 (setq temp-two 0) → 0 (dotimes (temp-one 10 t) (incf temp-two)) → T temp-two → 10
Here is an example of the use of
dotimes in processing strings:
;;; True if the specified subsequence of the string is a ;;; palindrome (reads the same forwards and backwards). (defun palindromep (string &optional (start 0) (end (length string))) (dotimes (k (floor (- end start) 2) t) (unless (char-equal (char string (+ start k)) (char string (- end k 1))) (return nil)))) (palindromep "Able was I ere I saw Elba") → T (palindromep "A man, a plan, a canal--Panama!") → NIL (remove-if-not #'alpha-char-p ;Remove punctuation. "A man, a plan, a canal--Panama!") → "AmanaplanacanalPanama" (palindromep (remove-if-not #'alpha-char-p "A man, a plan, a canal--Panama!")) → T (palindromep (remove-if-not #'alpha-char-p "Unremarkable was I ere I saw Elba Kramer, nu?")) → T (palindromep (remove-if-not #'alpha-char-p "A man, a plan, a cat, a ham, a yak, a yam, a hat, a canal--Panama!")) → T
do, dolist, tagbody
go may be used within the body of
dotimes to transfer control to a statement labeled by a tag.