12 <concept xml:lang="en" id="GUID-074F3499-54FE-58BC-A0F4-D8EA632AF76B"><title>Externalising a Swizzle</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>Typically, externalizing a Swizzle is a two stage process which involves:</p> <ul><li id="GUID-EB65444C-7693-53BB-B3B8-D072F80B0CFD"><p>externalizing the in-memory object which the Swizzle represents, to its own stream</p> </li> <li id="GUID-90A275E2-B9C2-5162-ADBA-1035102A93E1"><p>externalizing the resulting stream ID.</p> </li> </ul> <p>For example, given a container type object, <codeph>CClassABC</codeph>, with a data member <codeph>TSwizzle&lt;CClassB&gt; iB</codeph> representing a <codeph>CClassB</codeph> object in memory, the diagram below illustrates the result of storing the container object.</p> <fig id="GUID-E32084CE-13EE-5F32-A62E-A57C30768AE2"><image href="GUID-530AB0D9-BE70-5892-BFBA-213687CA62D1_d0e596325_href.png" placement="inline"/></fig> <p>The following code fragments illustrates the process.</p> <p><codeph>iB</codeph> is a <codeph>CClassB</codeph> type component of a class <codeph>CClassABC</codeph>, and is represented by a Swizzle. The data member is defined as:</p> <codeblock id="GUID-9751293C-D5CD-5397-97F3-C0E5F4A877DF" xml:space="preserve">class CCClassABC : public CBase

    12 <concept xml:lang="en" id="GUID-074F3499-54FE-58BC-A0F4-D8EA632AF76B"><title>Externalising a Swizzle</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>Typically, externalizing a Swizzle is a two stage process which involves:</p> <ul><li id="GUID-EB65444C-7693-53BB-B3B8-D072F80B0CFD"><p>externalizing the in-memory object which the Swizzle represents, to its own stream</p> </li> <li id="GUID-90A275E2-B9C2-5162-ADBA-1035102A93E1"><p>externalizing the resulting stream ID.</p> </li> </ul> <p>For example, given a container type object, <codeph>CClassABC</codeph>, with a data member <codeph>TSwizzle&lt;CClassB&gt; iB</codeph> representing a <codeph>CClassB</codeph> object in memory, the diagram below illustrates the result of storing the container object.</p> <fig id="GUID-E32084CE-13EE-5F32-A62E-A57C30768AE2"><image href="GUID-530AB0D9-BE70-5892-BFBA-213687CA62D1_d0e584031_href.png" placement="inline"/></fig> <p>The following code fragments illustrates the process.</p> <p><codeph>iB</codeph> is a <codeph>CClassB</codeph> type component of a class <codeph>CClassABC</codeph>, and is represented by a Swizzle. The data member is defined as:</p> <codeblock id="GUID-9751293C-D5CD-5397-97F3-C0E5F4A877DF" xml:space="preserve">class CCClassABC : public CBase

    48 </codeblock> <p>At this point, the Swizzle still represents the <codeph>CClassB</codeph> object as a pointer, and the object itself is still in memory.</p> <p>The mechanism underlying the implementation of the stream <codeph>operator&lt;&lt;</codeph>, assumes that the stream ID associated with the Swizzle has been placed in the store map. It also assumes that the <codeph>RStoreWriteStream</codeph> object has been constructed, specifying the store map as an externalizer.</p> <p>The end result of the operation <codeph>aStream &lt;&lt; iB;</codeph>, is to externalise, to the stream, the stream ID associated with the Swizzle <codeph>iB</codeph>. The following diagram shows this:</p> <fig id="GUID-0958AA91-661B-54EA-B540-067DB933169D"><image href="GUID-DD764F2C-365A-5A5C-9412-4AF2EDB16924_d0e596509_href.png" placement="inline"/></fig> </conbody></concept>

    48 </codeblock> <p>At this point, the Swizzle still represents the <codeph>CClassB</codeph> object as a pointer, and the object itself is still in memory.</p> <p>The mechanism underlying the implementation of the stream <codeph>operator&lt;&lt;</codeph>, assumes that the stream ID associated with the Swizzle has been placed in the store map. It also assumes that the <codeph>RStoreWriteStream</codeph> object has been constructed, specifying the store map as an externalizer.</p> <p>The end result of the operation <codeph>aStream &lt;&lt; iB;</codeph>, is to externalise, to the stream, the stream ID associated with the Swizzle <codeph>iB</codeph>. The following diagram shows this:</p> <fig id="GUID-0958AA91-661B-54EA-B540-067DB933169D"><image href="GUID-DD764F2C-365A-5A5C-9412-4AF2EDB16924_d0e584215_href.png" placement="inline"/></fig> </conbody></concept>