code> then boolean values are compared for equality only.
		The default value for this field is <code>nil</code>.
	</dd>
	
	<dt><code><b>envkey</b></code></dt>
	<dd>
		Special value used to identify a function environment retrieval.
		See method <code>error</code> for further information.
	</dd>
	
	<dt><code><b>environment</b></code></dt>
	<dd>
		Field that defines the function used to retrieve the environment of a function.
		If this field evaluates to <code>false</code> then function environments are igno