Databases
StackOverflow2013
Postsdbo
POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
    primarykey
    data
    text
    <p>I have been researching the Curiously Recurring Template Pattern to determine how I could use it to implement a Bridge Design Pattern.</p> <p>My problem is connecting, (wiring up), the IBridgeConnector::GetBridgeImpl method to the Bridge::GetBridgeImpl method since the overriding method is actually templated.</p> <p>Since virtual dispatch won't work in this case, what is the best way to point these methods to each other? Function Delegates? Is there a better pattern for this?</p> <p>How should this be done?</p> <p>Thanks for the help!</p> <p>Made the best code simplification I can without shared_ptrs everwhere and OpenGL and DirectX calls. :) Hopefully this will be useful to someone in the future!</p> <pre><code>#include &lt;string&gt; /********************************************************************/ class BridgePart { public: BridgePart * OtherPart; }; /********************************************************************/ // Connects a BridgeSource and a BridgeImplementation class BridgeConnector { public: static BridgeConnector * implementor; // Need a way, (Function Delegates?) to point this method // This method will loop until stack overflow. template &lt;typename ValueTemplateType&gt; BridgePart * GetBridgeImpl(ValueTemplateType * source) { return implementor-&gt;GetBridgeImpl&lt;ValueTemplateType&gt;(source); } }; BridgeConnector * BridgeConnector::implementor = nullptr; /********************************************************************/ // Where the Magic is At, (CRTP) template &lt;typename BridgeImplementationTemplateType&gt; class Bridge : public BridgeConnector { public: template &lt;typename ValueTemplateType&gt; IBridgePart * GetBridgeImpl(IBridgePart * source) { // NOTE: This method never gets called. // CRTP Magic Here to Semi-Specify Pure Virtual Methods return static_cast&lt;BridgeImplementationTemplateType&gt;(this) -&gt;GetBridgeImpl( (ValueTemplateType) source); } }; /********************************************************************/ class BridgeImplementation1 : public Bridge&lt;BridgeImplementation1&gt;, public BridgePart { public: class CustomImpl : public BridgePart { public: template &lt;typename SourceTemplateType&gt; BridgePart(SourceTemplateType source){} /* Does proprietary stuff. */ }; template &lt;typename ValueTemplateType&gt; BridgePart * GetBridgeImpl(ValueTemplateType &amp; source) { return new CustomImpl&lt;ValueTemplateType&gt;(source); } // Constructor BridgeImplementation1() { } }; /********************************************************************/ class BridgeSource1 : public BridgePart {}; class BridgeSource2 : public BridgePart {}; class Client { BridgeSource1 source1; BridgeSource2 source2; BridgeConnector * connector; bool usingImpl1; Client() { usingImpl1 = true; // from config file. connector = new BridgeConnector(); connector-&gt;implementor = usingImpl1 ? (BridgeConnector *) new BridgeImplementation1() : nullptr; // (BridgeConnector *) new BridgeImplementation2(); // removed to shorten code. } void Init() { source1.OtherPart = connector-&gt;GetBridgeImpl&lt;BridgeSource1&gt;(&amp; source1); source2.OtherPart = connector-&gt;GetBridgeImpl&lt;BridgeSource2&gt;(&amp; source2); } }; </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USDave Schweisguth
    1. USe.s. kohen
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
      1. This table or related slice is empty.
      1. VTDownMod
    1. COUse a debugger, and step through the code line by line (stepping into the functions called), and you will see quite quickly why you get the stack overflow. As a hint, you call `LoadDriver` with a pointer, and keep calling `LoadDriver` with a pointer.
      singulars
      1. POHow to use Curiously Recurring Template Pattern for Bridge Pattern?
      1. USSome programmer dude
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload