In file &lt;boost/shared_ptr.hpp&gt;, I find the following function:<br>/begin quote<br>template&lt;class Y, class D&gt; shared_ptr(Y * p, D d): px(p), pn(p, d)<br>&nbsp;&nbsp;&nbsp; {<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; detail::sp_enable_shared_from_this( pn, p, p );
<br>&nbsp;&nbsp;&nbsp; }<br>/end quote<br>If I use it as follows:&quot;boost::shared_ptr&lt;Investment&gt; pInv(0,getRidOfInvestment)&quot;,it will not compile.But when I use:&quot;boost::shared_ptr&lt;Investment&gt; pInv(static_cast&lt;Investment*&gt;(0),getRidOfInvestment)&quot;,it can be compiled.
<br>The constructor's first parameter is Y*,i.e.,a pointer to Y.And 0 can be interpreted as a pointer to Y,too.&nbsp; Why&nbsp; can't zero be treated as a pointer to Y here?<br><br>I will be appreciative if anyone can give me some 
suggestions.Thank you!<br><br>hzhuo<br>July,14th<br>