Then you should use a custom generator and not Arbitrary.<br><br><div class="gmail_quote">On Sat, Jan 8, 2011 at 9:39 PM, Ivan Lazar Miljenovic <span dir="ltr">&lt;<a href="mailto:ivan.miljenovic@gmail.com">ivan.miljenovic@gmail.com</a>&gt;</span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">On 9 January 2011 07:20, Henning Thielemann<br>
<div class="im">&lt;<a href="mailto:lemming@henning-thielemann.de">lemming@henning-thielemann.de</a>&gt; wrote:<br>
&gt;<br>
&gt; If there are multiple equally natural instances, then there should not<br>
&gt; be one at all.<br>
<br>
</div>It depends what you mean.  In my case, I wanted the String instance<br>
for Arbitrary to follow certain rules (can&#39;t be the textual<br>
representation of a number, can&#39;t have certain characters in it,<br>
etc.).<br>
<div class="im"><br>
--<br>
Ivan Lazar Miljenovic<br>
<a href="mailto:Ivan.Miljenovic@gmail.com">Ivan.Miljenovic@gmail.com</a><br>
<a href="http://IvanMiljenovic.wordpress.com" target="_blank">IvanMiljenovic.wordpress.com</a><br>
<br>
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