Function: erc-networks--id-qualifying-prefix-length

erc-networks--id-qualifying-prefix-length is a byte-compiled function defined in erc-networks.el.gz.

Signature

(erc-networks--id-qualifying-prefix-length NID-A NID-B)

Documentation

Return length of common initial prefix of NID-A and NID-B.

Return nil when no such sequence exists (instead of zero).

Source Code

;; Defined in /usr/src/emacs/lisp/erc/erc-networks.el.gz
(defun erc-networks--id-qualifying-prefix-length (nid-a nid-b)
  "Return length of common initial prefix of NID-A and NID-B.
Return nil when no such sequence exists (instead of zero)."
  (when-let* ((a (erc-networks--id-qualifying-parts nid-a))
              (b (erc-networks--id-qualifying-parts nid-b))
              (n (min (length a) (length b)))
              ((> n 0))
              ((equal (elt a 0) (elt b 0)))
              (i 1))
    (while (and (< i n)
                (equal (elt a i)
                       (elt b i)))
      (cl-incf i))
    i))