count-words-example FunctionA word count command could count words in a line, paragraph, region,
or buffer. What should the command cover? You could design the
command to count the number of words in a complete buffer. However,
the Emacs tradition encourages flexibility—you may want to count
words in just a section, rather than all of a buffer. So it makes
more sense to design the command to count the number of words in a
region. Once you have a command to count words in a region, you can,
if you wish, count words in a whole buffer by marking it with
C-x h (mark-whole-buffer).
Clearly, counting words is a repetitive act: starting from the
beginning of the region, you count the first word, then the second
word, then the third word, and so on, until you reach the end of the
region. This means that word counting is ideally suited to recursion
or to a while loop.