To read in characters that belong to an arbitrary set of your choice,
use the @samp{%[} conversion. You specify the set between the @samp{[}
character and a following @samp{]} character, using the same syntax used
-in regular expressions. As special cases:
+in regular expressions for explicit sets of characters. As special cases:
@itemize @bullet
@item
The @samp{%[} conversion does not skip over initial whitespace
characters.
+Note that the @dfn{character class} syntax available in character sets
+that appear inside regular expressions (such as @samp{[:alpha:]}) is
+@emph{not} available in the @samp{%[} conversion.
+
Here are some examples of @samp{%[} conversions and what they mean:
@table @samp