<div dir="ltr"><div style="" id="gt-input-tool"><div><span class=""></span></div></div><div id="gt-src-c" class=""><div id="gt-src-p"> </div> </div> <div id="gt-res-content" class=""><div style=""><span id="result_box" class="" lang="en"><span class="">Hello list,<br></span></span></div><div dir="ltr" style="zoom:1"><span id="result_box" class="" lang="en"><span class=""><br>In some situations</span><span>, would be</span> <span class="">very interesting to determine</span> <span class="">whether the value of</span> <span class="">a primitive</span> <span class="">variable is</span> <span class="">initialized</span> <span class="">or not.</span> <span class="">For example</span><span>,</span> <span class="">fields in database records can</span> <span class="">contain null values</span><span>.</span> <span class="">By implementing</span> <span class="">an ORM</span><span>, it would be</span> <span class="">interesting to</span> <span class="">represent these</span> <span class="">null values</span> <span class="">in the properties</span> <span class="">of objects.</span><br><br> <span class="">Java</span> <span class="">has the</span> so called <span class="">Primitives</span> <span class="">Class</span> <span class="">Wrappers</span><span class="">,</span> <span class="">where each</span> <span class="">primitive type</span> <span class="">(</span><span>int,</span> <span class="">boolean</span> <span class="">...</span><span>)</span> <span class=""></span></span><span id="result_box" class="" lang="en"><span class=""><span id="result_box" class="" lang="en"><span class="">has a corresponding</span> <span class="">wrapper class</span></span></span><span class=""></span> <span class="">(Integer</span><span>, Boolean</span> <span class="">...</span><span>)</span><span>.</span> <span class="">By using class wrappers</span> <span class="">you can represent</span> <span class="">null values</span> <span class="">in primitive types</span> <span class="">through</span> <span class="">null</span> <span class="">class instances</span> <span class="">references.</span><br><br>Using class wrappers in FPC is not feasible due to memory management issues (the programmer needs to worry about the lifetime of the instances and free the instances </span><span id="result_box" class="" lang="en"><span id="result_box" class="" lang="en"><span class="">manually</span></span>).<br><br></span></div><div style=""><span id="result_box" class="" lang="en">Perhaps, a solution in FPC would be using primitive record wrappers with custom records operators. <br></span></div><div dir="ltr" style="zoom:1"><span id="result_box" class="" lang="en"><br></span></div><div style=""><span id="result_box" class="" lang="en">What do you think about it? Is there any other solution?<br><br></span></div><div style=""><span id="result_box" class="" lang="en">Regards<br></span></div><div dir="ltr" style="zoom:1"><span id="result_box" class="" lang="en"><span class=""></span><span class=""></span></span></div></div></div>