    {% comment %}
    {% include navbar.html %}
    {% endcomment %}

Jekyll uses the [Liquid templating system][1]. So whatever works for Liquid works for Jekyll.

    {% comment %}
    this is commented out
    {% endcomment %}

https://help.shopify.com/themes/liquid/tags/theme-tags#comment

  [1]: https://help.shopify.com/themes/liquid


Given an array of `[Any]` that has a mix of optional and non optional values, e.g:

    let int:Int? = 1
    let str:String? = &quot;foo&quot;
    
    let values:[Any] = [int,2,str,&quot;bar&quot;]

How can we extract the value of the `Optional` in the `Any` type (if there is one) so we can create a generic print function that only prints out the values.

E.g. this printArray function goes through and prints each element:

    func printArray(values:[Any]) {
        for i in 0..&lt;values.count {
            println(&quot;value[\(i)] = \(values[i])&quot;)
        }
    }
    
    printArray(values)

Which will output:

    value[0] = Optional(1)
    value[1] = 2
    value[2] = Optional(&quot;foo&quot;)
    value[3] = bar

How can we change it so it only prints the underlying value so that it unwraps the value if it&#39;s Optional? e.g:

    value[0] = 1
    value[1] = 2
    value[2] = foo
    value[3] = bar

---

### Update Progress...

It can work when changing the argument to `[Any?]`, e.g:

    let values:[Any?] = [int,2,str,&quot;bar&quot;]
    
    func printArray(values:[Any?]) {
        for i in 0..&lt;values.count {
            println(&quot;value[\(i)] = \(values[i]!)&quot;)
        }
    }

    printArray(values)

Which will print the desired:

    value[0] = 1
    value[1] = 2
    value[2] = foo
    value[3] = bar

But would still like to see how we can unwrap an Optional from `Any` as this is what `MirrorType.value` returns making it difficult to extract the Optional value, e.g:

    class Person {
        var id:Int = 1
        var name:String?
    }
    
    var person = Person()
    person.name = &quot;foo&quot;
    
    var mt:MirrorType = reflect(person)
    for i in 0 ..&lt; mt.count {
        let (name, pt) = mt[i]
        println(&quot;\(name) = \(pt.value)&quot;)
    }

Prints out:

    id = 1
    name = Optional(&quot;foo&quot;)

When I need:

    id = 1
    name = foo



How to unwrap an optional value from Any type?

Please, answers here all refer to a something called process.env.NODE_ENV, but `echo $process.env.NODE_ENV` from the command line did not work. Any ideas?

Is there a way to display NODE_ENV from the command line?

Is there a way to comment out an include statement inside an HTML file using Jekyll?

For example I have this inside one of my HTML files that I&#39;d like to temporarily comment out. Standard	HTML comment doesn&#39;t seem to work.

    {% include navbar.html %}			



Comment out an include statement inside an HTML file using Jekyll

Is there a way to comment out an include statement inside an HTML file using Jekyll?
For example I have this inside one of my HTML files that I'd like to temporarily comment out. Standard	HTML comment doesn't seem to work.
<pre><code class="hljs language-makefile">{% include navbar.html %}			
</code></pre>

Recently I found that there is, possibly, a new way of commenting in HTML5.

Instead of the typical `&lt;!-- --&gt;` multi-line commenting I&#39;ve read about,  I *thought* I noticed that my IDE made a regular `&lt;!div &gt;` commented out. So I tested it out, and to my surprise Chrome had commented out that tag. It *only* commented out the tag and not the contents of the div, so I had to comment out the closer `&lt;!/div&gt;` to avoid closing other divs.

I tested another and it appears that generally putting an exclamation marker in front of the opening of any tag, this symbol `&lt;`, makes that tag commented out.

Is this actually new? Is it bad practice? It is actually very convenient, but is it practical yet (if not new)?

**Extra details:**

Although a syntax error or misinterpretations of this particular syntax is a good reason, how come Chrome *actually* renders them as full comments?

**The code is written as**:

```lang-none
&lt;!div displayed&gt; some text here that is still displayed &lt;!/div&gt;
```

**And then it is rendered as**:

```lang-none
&lt;!--div displayed--&gt; some text here that is still displayed &lt;!--/div--&gt;
```




Does HTML5 change the standard for HTML commenting?

What&#39;s the difference between 

    /**
     * comment
     *
     *
     */

and 

    /*
     * 
     * comment
     *
     */

in Java? When should I use them?

/** and /* in Java Comments

The following code produces the output &quot;Hello World!&quot; (no really, try it).

    public static void main(String... args) {

       // The comment below is not a typo.
       // \u000d System.out.println(&quot;Hello World!&quot;);
    }

The reason for this is that the Java compiler parses the Unicode character `\u000d` as a new line and gets transformed into:

    public static void main(String... args) {

       // The comment below is not a typo.
       //
       System.out.println(&quot;Hello World!&quot;);
    }

Thus resulting into a comment being &quot;executed&quot;.

Since this can be used to &quot;hide&quot; malicious code or whatever an evil programmer can conceive, **why is it allowed in comments**?

Why is this allowed by the Java specification?


Why is executing Java code in comments with certain Unicode characters allowed?

I&#39;ve found this C program from the web:

    #include &lt;stdio.h&gt;
    
    int main(){
        
        printf(&quot;C%d\n&quot;,(int)(90-(-4.5//**/
        -4.5)));
        
        return 0;
    }

The interesting thing with this program is that when it is compiled and run in C89 mode, it prints `C89` and when it is compiled and run in C99 mode, it prints `C99`. But I am not able to figure out how this program works.

Can you explain how the second argument of `printf` works in the above program?

How does the below program output `C89` when compiled in C89 mode and `C99` when compiled in C99 mode?

How can I add comment to column in PostgreSQL?

    create table session_log (
                    UserId int index not null,
                    PhoneNumber int index); 

Adding comment to column when I create table in PostgreSQL?

I am trying to set a `favicon.ico` for my github page, but it doesn&#39;t work. When I serve it locally I see the standard &quot;empty&quot; favicon and when I push it I see the facebook icon. Why is it so? I have the right `favicon.ico` in the root directory of my project and I added the line 

    &lt;link rel=&quot;shortcut icon&quot; type=&quot;image/x-icon&quot; href=&quot;/favicon.ico&quot;&gt;

to the relevant `default.html`. You can see the sources here: https://github.com/drorata/drorata.github.io

Unable to set favicon using Jekyll and github pages

I am trying to add a new post to my Jekyll site, but I cannot see it on the generated pages when I run `jekyll serve`.

What are some common reasons for a Jekyll post to not be generated?

Jekyll post not generated

When calling items from an array in a Liquid template, how do you call `does not contain` or `not in array`?


Does Liquid have a &quot;does not contain&quot; or &quot;not in array&quot; operator?

There are many themes for Jekyll, e.g. https://github.com/jekyll/jekyll/wiki/Themes.

What is the easiest way to switch to a new theme in an EXISTING Jekyll installation?



Switch theme in an existing Jekyll installation

I used `sudo bundle install` and that might be the cause of the issue? 

Now I have:

- `gem -v` 2.6.14
- `ruby -v` ruby 2.3.5p376 (2017-09-14 revision 59905) [x86_64-darwin15]
- `jekyll -v` jekyll 3.6.2
- `bundle -v`Bundler version 1.16.0.pre.3

I&#39;m getting the following error when trying to run `bundle exec jekyll serve` or just `jekyll serve`

```
/Users/myusername/.rvm/rubies/ruby-2.3.5/lib/ruby/site_ruby/2.3.0/rubygems.rb:271:in `find_spec_for_exe&#39;: can&#39;t find gem bundler (&gt;= 0.a) (Gem::GemNotFoundException)
	from /Users/myusername/.rvm/rubies/ruby-2.3.5/lib/ruby/site_ruby/2.3.0/rubygems.rb:299:in `activate_bin_path&#39;
	from /Users/myusername/.rvm/gems/ruby-2.3.5/bin/bundle:23:in `&lt;main&gt;&#39;
	from /Users/myusername/.rvm/gems/ruby-2.3.5/bin/ruby_executable_hooks:15:in `eval&#39;
	from /Users/myusername/.rvm/gems/ruby-2.3.5/bin/ruby_executable_hooks:15:in `&lt;MacBooMacBook-MacBook-MacBook-Pro-MacBook-PrMacBook-MacBooMacBMaMacBMaMaMaMaMaMaMaMaMacBMaMaMaMacBMa
```

Also, when accessing the folder in which I have my blog `cd my_path` I get the following message:

&gt; VM used your Gemfile for selecting Ruby, it is all fine - Heroku does that too,
you can ignore these warnings with &#39;rvm rvmrc warning ignore /Library/WebServer/Documents/blog/Gemfile&#39;.
To ignore the warning for all files run &#39;rvm rvmrc warning ignore allGemfiles&#39;.
Unknown ruby interpreter version (do not know how to handle): RUBY_VERSION.

I&#39;ve no idea how to solve this. I just want to create my static blog and honestly I have no idea about Ruby, Gem or Bundle :) So I would appreciate some insights!

Content Type	Original Author	Original Content on Stackoverflow
Question	Amit	View Question on Stackoverflow
Solution 1 - Comments	David Jacquel	View Answer on Stackoverflow
Solution 2 - Comments	mccambridge	View Answer on Stackoverflow

Comment out an include statement inside an HTML file using Jekyll

Comments Problem Overview

Comments Solutions

Solution 1 - Comments

Solution 2 - Comments

Is there a way to display NODE_ENV from the command line?

How to unwrap an optional value from Any type?

Attributions