
	</dd>
	
	<dt><code><b>_missing</b></code></dt>
	<dd>
		String that defines the format of the error message generated when an command-line option is provided without value.
		The default value for this field is <code>"no value defined for option '%s'"</code>.
	</dd>

	<dt><code><b>_norepeat</b></code></dt>
	<dd>
		String that defines the format of the error message generated when a same command-line option is provided more than once.
		If this field evaluates to false then repeated command-line option are 