<para>
Both <literal>source</literal> and <literal>target</literal> can be any
- non-null string, with a maximum of 255 bytes. The cost parameters
+ non-null string, with a maximum of 255 characters. The cost parameters
specify how much to charge for a character insertion, deletion, or
substitution, respectively. You can omit the cost parameters, as in
the second version of the function; in that case they all default to 1.
- <literal>levenshtein_less_equal</literal> is accelerated version of
- levenshtein function for low values of distance. If actual distance
- is less or equal then max_d, then <literal>levenshtein_less_equal</literal>
- returns accurate value of it. Otherwise this function returns value
- which is greater than max_d.
+ </para>
+
+ <para>
+ <function>levenshtein_less_equal</function> is an accelerated version of the
+ Levenshtein function for use when only small distances are of interest.
+ If the actual distance is less than or equal to <literal>max_d</>,
+ then <function>levenshtein_less_equal</function> returns the correct
+ distance; otherwise it returns some value greater than <literal>max_d</>.
+ If <literal>max_d</> is negative then the behavior is the same as
+ <function>levenshtein</function>.
</para>
<para>