Templates are compiled (atleast) twice:  

 1. Without Instantiation the template code itself is checked for syntax.  
Eg: Any syntax errors such as `;` etc.

 2. At the time of instantiation(when the exact type is known), the template code is checked again to ensure all calls are valid for that particular type.  
Eg: The template might in turn call to functions which might not be present for that particular type.

This is called as **Two Phase Lookup.**

I would like to know your opinion about javascript template engine, which one you think is better in terms of performance?

I found some links where people do benchmarking:

[http://jsperf.com/jquery-template-table-performance/15][1]

[http://jsperf.com/jquery-template-table-performance/8][2]

[http://www.viget.com/extend/benchmarking-javascript-templating-libraries/][3]


  [1]: http://jsperf.com/jquery-template-table-performance/15
  [2]: http://jsperf.com/jquery-template-table-performance/8
  [3]: http://www.viget.com/extend/benchmarking-javascript-templating-libraries/

What Javascript Template Engines you recommend?

I have read [this question][1] but it doesn&#39;t exactly answer my question.
Unfortunately, it looks like things have changed in in the XHR object since I last looked at AJAX, so it is no longer possible to directly access `responseText` before it is finished being populated.

I have to write a page that uses AJAX (preferably jQuery, but I am open to suggestions) to retrieve CSV data via HTTP from a server I have no control over.  The response data could be quite large; a megabyte of text is not uncommon.

The server is stream-friendly. Is there still any way to get access to a stream of data as it is being returned, directly from JavaScript?

I do have the option of writing some PHP code that lives in the middle and uses some sort of &quot;Comet&quot; tech (long-polling, EventSource, etc), but I would prefer to avoid that if possible.

*In case it is relevant, assume for this question that users have the latest version of Firefox/Chrome/Opera and old browser compatibility is not an issue.*


  [1]: https://stackoverflow.com/questions/6093103/jquery-ajax-display-data-as-it-comes-in

jQuery read AJAX stream incrementally?

What does it mean that compiler is using two phase lookup in order to compile template class?

Two phase lookup - explanation needed

<p>What does it mean that compiler is using two phase lookup in order to compile template class?</p>


I am copying N bytes from `pSrc` to `pDest`. This can be done in a single loop:

    for (int i = 0; i &lt; N; i++)
        *pDest++ = *pSrc++

Why is this slower than `memcpy` or `memmove`? What tricks do they use to speed it up?


Why are memcpy() and memmove() faster than pointer increments?

I have a char* and the data length that I&#39;m receiving from a library, and I need to pass the data to a function that takes an istream.

I know I can create a stringstream but that will copy all the data. And also, the data will surely have 0s since it&#39;s a zip file, and creating a stringstream will take the data until the first 0 I think.

Is there any way to create an istream from a char* and it&#39;s size without copying all the data?

Get an istream from a char*

In particular, I am looking for a blocking queue. Is there such a thing in C++11? If not, what are my other options? I really don&#39;t want to go down to the thread level myself anymore. Way too error-prone.

Are there any concurrent containers in C++11?

To prevent copying a class, you can very easily declare a private copy constructor / assignment operators. But you can also inherit `boost::noncopyable`.

What are the advantages / disadvantages of using boost in this case?

What are the advantages of boost::noncopyable

I hear that `reinterpret_cast` is implementation defined, but I don&#39;t know what this really means. Can you provide an example of how it can go wrong, and it goes wrong, is it better to use C-Style cast?

Reinterpret_cast vs. C-style cast

&gt; **Possible Duplicate:**  
&gt; [Officially, what is typename for?](https://stackoverflow.com/questions/1600936/officially-what-is-typename-for)  
&gt; [Where and why do I have to put the template and typename keywords?](https://stackoverflow.com/questions/610245/where-and-why-do-i-have-to-put-template-and-typename)

&lt;!-- End of automatically inserted text --&gt;

consider the code below:

    template&lt;class K&gt;
    class C {
        struct P {};
        vector&lt;P&gt; vec;
        void f();
    };
    
    template&lt;class K&gt; void C&lt;K&gt;::f() {
        typename vector&lt;P&gt;::iterator p = vec.begin();
    }

Why is the &quot;typename&quot; keyword necessary in this example?
Are there any other cases where &quot;typename&quot; must be specified?



When is the &quot;typename&quot; keyword necessary?

I&#39;m new to Mustache.

Many templating languages (e.g., **Django** / **Jinja**) will let you extend a &quot;parent&quot; template like so...

### base.html
    &lt;html&gt;&lt;head&gt;&lt;/head&gt;
        &lt;body&gt;
        {% block content %}{% endblock %}
        &lt;/body&gt;
    &lt;/html&gt;

### frontpage.html
    {% extends &quot;base.html&quot; %}
    {% block content %}&lt;h1&gt;Foobar!&lt;/h1&gt;{% endblock %}


### rendered frontpage.html
    &lt;html&gt;&lt;head&gt;&lt;/head&gt;
        &lt;body&gt;
        &lt;h1&gt;Foobar!&lt;/h1&gt;
        &lt;/body&gt;
    &lt;/html&gt;


I&#39;m aware of Mustache&#39;s *partials* (e.g., `{{&gt;content}}`), but those seem to be just *includes*.

Does template extension exist for Mustache? Or, failing that, is there at least some design pattern that effectively turns *includes* into template extension equivalents.

Can Mustache Templates do template extension?

I have an abstract class (I know that it will not compile this way, but it&#39;s for comprehension of what I want to do) :

    class AbstractComputation {
        public:
            template &lt;class T&gt; virtual void setData(std::string id, T data);
            template &lt;class T&gt; virtual T getData(std::string id);
    };
    
    class Computation : public AbstractComputation {
        public:
            template &lt;class T&gt; void setData(std::string id, T data);
            template &lt;class T&gt; T getData(std::string id, T data);
    };

So when I call `setData&lt;double&gt;(&quot;foodouble&quot;, data)` I want the double identified by `foodouble` (internal mechanism which is not the main concern here) to be set to the double data.

So how to do that? 

I think that there may be a mean by typing something like `virtual void setData&lt;double&gt;(std::string id, double data)` but I don&#39;t know how to do it.


C++ Virtual template method

Can some one please describe the usage of the following characters which is used in ERB file:

    &lt;%   %&gt;
    &lt;%=  %&gt;
    &lt;%  -%&gt;
    &lt;%#  %&gt;

what&#39;s the usage of each one ? 

What is the difference between &lt;%, &lt;%=, &lt;%# and -%&gt; in ERB in Rails?

    mydict = {&quot;key1&quot;:&quot;value1&quot;, &quot;key2&quot;:&quot;value2&quot;}

The regular way to lookup a dictionary value in a Django template is `{{ mydict.key1 }}`,  `{{ mydict.key2 }}`. What if the key is a loop variable? ie:

    {% for item in list %} # where item has an attribute NAME
      {{ mydict.item.NAME }} # I want to look up mydict[item.NAME]
    {% endfor %}

`mydict.item.NAME` fails. How to fix this?


Content Type	Original Author	Original Content on Stackoverflow
Question	smallB	View Question on Stackoverflow
Solution 1 - C++	Alok Save	View Answer on Stackoverflow

Two phase lookup - explanation needed

C++ Problem Overview

C++ Solutions

Solution 1 - C++

jQuery read AJAX stream incrementally?

What Javascript Template Engines you recommend?

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