    :help key-notation

says:

    notation    meaning            equivalent  decimal    value(s)
    -----------------------------------------------------------------------
    &lt;CR&gt;        carriage return        CTRL-M    13       *carriage-return*
    &lt;Return&gt;    same as &lt;CR&gt;                              *&lt;Return&gt;*
    &lt;Enter&gt;     same as &lt;CR&gt;                              *&lt;Enter&gt;*

Mappings often involve Ex commands and you must press `&lt;CR&gt;` to execute them so it&#39;s included in the mapping.

### Why `&lt;special keys&gt;`?

While you can use literal keys in mapping definitions (the Enter key would appear as `^M`, or even just as an additional new line, depending on the settings), Vim provides a special key notation for key (combinations), so that it is easier to define (you don&#39;t have to use `i_CTRL-V` to literally insert the special character) and understand (`&lt;A-a&gt;` better expresses the intention than the equivalent `&#225;`) the mappings.

See `:help key-notation` for a list and explanation.

### Why `&lt;CR&gt;`?

As many mappings invoke Ex commands (e.g. `:w`) and therefore have to switch from _normal_ to _command-line_ mode, they have to conclude the command with `&lt;Enter&gt;` (or `&lt;CR&gt;`), just as you would when manually typing the command.

The `&lt;CR&gt;` in `vim` mappings is the [carriage return](http://en.wikipedia.org/wiki/Carriage_return) usually the &lt;kbd&gt;Enter&lt;/kbd&gt; on your keyboard.

`&lt;CR&gt;` in a mapping corresponds to the &lt;kbd&gt;Enter&lt;/kbd&gt; key just like `a` in a mapping corresponds to the &lt;kbd&gt;A&lt;/kbd&gt; key. Ley&#39;s say you have this mapping

    :map &lt;f8&gt; :wq&lt;cr&gt;

This will map &lt;kbd&gt;F8&lt;/kbd&gt; to the key sequence &lt;kbd&gt;:&lt;/kbd&gt;&lt;kbd&gt;W&lt;/kbd&gt;&lt;kbd&gt;Q&lt;/kbd&gt;&lt;kbd&gt;Enter&lt;/kbd&gt; (which would save the current buffer and quit).

It&#39;s basically a means to say &quot;this is the end&quot;, see [map](http://vimdoc.sourceforge.net/htmldoc/map.html):

&gt; When you have a mapping that contains an [Ex](http://vimdoc.sourceforge.net/htmldoc/intro.html#Ex) command, you need to put a line
terminator after it to have it executed.  The use of &lt;CR&gt; is recommended for
this. Example:
&gt;&gt;    `:map  _ls  :!ls -l %&lt;CR&gt;:echo &quot;the end&quot;&lt;CR&gt;`

also,

    &lt;CR&gt;    [count] lines downward, on the first non-blank character |linewise|.

When I run the following code in Python 3.3:

    import urllib
    tempfile = urllib.request.urlopen(&quot;http://yahoo.com&quot;)

I get the following error:

![enter image description here][1]


I did this too to verify:

![enter image description here][2]


What am I doing wrong?


  [1]: http://i.stack.imgur.com/7AoY2.jpg
  [2]: http://i.stack.imgur.com/xpHhS.jpg

AttributeError: &#39;module&#39; object has no attribute &#39;request&#39;

I&#39;m getting error in this code, I&#39;m trying to do an event where in when the page is load, it will do the event. But the problem is when I go to other function, but same page, it gets a error of null on that variable. It has no problem when I execute this codes, but when I&#39;m on other part of my codes this error occurs. &lt;br&gt;&lt;br&gt;

Uncaught TypeError: Cannot read property &#39;value&#39; of null  

    $(document).ready(function(){
          
          
          var str = document.getElementById(&quot;cal_preview&quot;).value;
          var str1 = document.getElementById(&quot;year&quot;).value;
          var str2 = document.getElementById(&quot;holiday&quot;).value;
          var str3 = document.getElementById(&quot;cal_option&quot;).value;
       
    
            if (str==&quot;&quot; &amp;&amp; str1==&quot;&quot; &amp;&amp; str2==&quot;&quot; &amp;&amp; str3==&quot;&quot; )
              {
                document.getElementById(&quot;calendar_preview&quot;).innerHTML=&quot;&quot;;
                  return;
                } 
              if (window.XMLHttpRequest)
              {// code for IE7+, Firefox, Chrome, Opera, Safari
                xmlhttp=new XMLHttpRequest();
              }
              else
              {// code for IE6, IE5
                xmlhttp=new ActiveXObject(&quot;Microsoft.XMLHTTP&quot;);
              }
    
              xmlhttp.onreadystatechange=function()
              {
                if (xmlhttp.readyState==4 &amp;&amp; xmlhttp.status==200)
                  {
                    document.getElementById(&quot;calendar_preview&quot;).innerHTML=xmlhttp.responseText;
                  }
              }
              
            var url = calendar_preview_vars.plugin_url + &quot;?id=&quot; + str +&quot;&amp;&quot;+&quot;y=&quot;+str1+&quot;&amp;&quot;+&quot;h=&quot;+str2+&quot;&amp;&quot;+&quot;opt=&quot;+str3;
            xmlhttp.open(&quot;GET&quot;,url,true);
            xmlhttp.send(); 
        
    
     });

Uncaught TypeError: Cannot read property &#39;value&#39; of null

I see `&lt;cr&gt;`s a lot in vim mappings, but what does it do?

What is the meaning of a &lt;CR&gt; at the end of some vim mappings?

<p>I see <code>&#x3C;cr></code>s a lot in vim mappings, but what does it do?</p>


I&#39;m learning Vim and can&#39;t wrap my head around the difference between `word` and `WORD`.

I got the following from the Vim manual.

&gt; A word consists of a sequence of letters, digits and underscores, or a
&gt; sequence of other non-blank characters, separated with white space
&gt; (spaces, tabs, &lt;EOL&gt;).  This can be changed with the &#39;iskeyword&#39;
&gt; option.  An empty line is also considered to be a word.
&gt; 
&gt; A WORD consists of a sequence of non-blank characters, separated with
&gt; white space.  An empty line is also considered to be a WORD.

I feel `word` and `WORD` are just the same thing. They are both a sequence of non-blank chars separated with white spaces. An empty line can be considered as both `word` and `WORD`.

Question:  
What&#39;s the difference between them?  
And why/when would someone use `WORD` over `word`?

I&#39;ve already done Google and SO search, but their search-engine interpret `WORD` as just `word` so it&#39;s like I&#39;m searching for `Vim word vs word` and of course won&#39;t find anything useful.

Vim: word vs WORD

Is it possible to change the python version used by syntastic for syntax checking?


As the Issue  https://github.com/scrooloose/syntastic/issues/385 indicates I could use virtual-env. But is it also possible just with syntastic or vim commands?

Switch Python Version for Vim &amp; Syntastic

I have four text files A.txt, B.txt, C.txt and D.txt
I have to perform a series of vim editing in all these files.
Currently how I am doing is open each files and do the same vim commands one by one.


Is it possible to make a script file which I can run from the command prompt, means without open the actual file for vim editing.

for example, if I have to perform the below vim commands after opening the A.txt file in vim editor:

    :g/^\s*$/d
    :%s/^/[/
    :%s/$.*$$\s\+$$.*$/\3\2\1
    :%s/$/]/
    :%s/design/test/

Is it possible to make a script file and put all these commands including `gvim A.txt` (first command in the file).
and edit run the script file from command prompt.

If it is possible, please let me know how to do it and how it can be done with single or multiple files at a time?



How to run a series of vim commands from command prompt

I know how to open a file in Vim from a terminal (`vim fileName`). What I can&#39;t figure out is how to open a file when I&#39;m already within Vim.

I tried `:r fileName`, but that appears to read (or append) the file into the unsaved buffer I have open. It creates a new file, because when I try to write it with `:w`, it asks for a filename.


How do you open a file from within Vim?

I&#39;m using putty on a Linux machine. My usual method for searching in vi is entering the slash &lt;kbd&gt;/&lt;/kbd&gt;, then my search string, enter, then go through all the matches by &lt;kbd&gt;n&lt;/kbd&gt; or &lt;kbd&gt;shift&lt;/kbd&gt; + &lt;kbd&gt;n&lt;/kbd&gt;.

I was wondering if vi had a feature like Eclipse&#39;s Incremental Search (&lt;kbd&gt;ctrl&lt;/kbd&gt; + &lt;kbd&gt;j&lt;/kbd&gt;), wherein as I type, it jumps to the next logical match. I think one of my office mates used to do it but I&#39;m not sure.

Vim incremental search

When do you use `map` vs `flatMap` in **RxJava**?

Say, for example, we want to map Files containing JSON into Strings that contain the JSON--

Using `map`, we have to deal with the `Exception` somehow. But how?:
    
    Observable.from(jsonFile).map(new Func1&lt;File, String&gt;() {
        @Override public String call(File file) {
            try {
                return new Gson().toJson(new FileReader(file), Object.class);
            } catch (FileNotFoundException e) {
                // So Exception. What to do ?
            }
            return null; // Not good :(
        }
    });

Using `flatMap`, it&#39;s much more verbose, but we can forward the problem down the chain of `Observables` and handle the error if we choose somewhere else and even retry:
    
    Observable.from(jsonFile).flatMap(new Func1&lt;File, Observable&lt;String&gt;&gt;() {
        @Override public Observable&lt;String&gt; call(final File file) {
            return Observable.create(new Observable.OnSubscribe&lt;String&gt;() {
                @Override public void call(Subscriber&lt;? super String&gt; subscriber) {
                    try {
                        String json = new Gson().toJson(new FileReader(file), Object.class);
    
                        subscriber.onNext(json);
                        subscriber.onCompleted();
                    } catch (FileNotFoundException e) {
                        subscriber.onError(e);
                    }
                }
            });
        }
    });

I like the simplicity of the `map`, but the error handling of `flatmap` (not the verbosity). I haven&#39;t seen any best practices on this floating around and I&#39;m curious how this is being used in practice.

When do you use map vs flatMap in RxJava?

Actually, I would say that both iOS `ViewControllers` and Android `Activities` have their lifecycle methods. For example an equivalent of `ViewController.viewDidLoad()` is `Activity.onCreate()` ?

Else I still need to know the equivalent of the other :

 - `OnStart()`
 - `OnRestart()`
 - `OnResume()`
 - `OnStop()`
 - `OnDestroy()`
 - `OnPause()`


What the equivalent of activity life cycle in iOS?

I&#39;m trying to map some Java classes using the Hibernate JPA implementation. My problem is that I can&#39;t use hardcoded Strings als column namens. You can see the error message I get in the picture below.


![enter image description here][1]


I&#39;m using OpenJPA as my Default JPA Provider and have already tried to change it.

IntelliJ Version 14.0.3


regards,


  [1]: http://i.stack.imgur.com/YRUbK.png

JPA Cannot resolve column/IntelliJ

I am using gulp. 

I would like to having one or multiple JS files (say jQuery) to combine them in one, minify it, and write it to a distribution folder. 

This is how I do it: 

    minifyJS([&#39;/js/myModule.file1.js&#39;,
              &#39;/js/myModule.file2.js&#39;], &#39;/dist/js&#39;, &#39;myModule&#39;)

the function: 

    function minifyJS(sourceFiles, destinationFolder, filenameRoot) {
        return gulp.src(sourceFiles)
            .pipe(plumber())
    
            // .pipe(sourcemaps.init()) here ???
            .pipe(concat(filenameRoot + &#39;.js&#39;))
            .pipe(sourcemaps.init()) // or here ???
    
            .pipe(gulp.dest(destinationFolder)) // save .js
            .pipe(uglify({ preserveComments: &#39;license&#39; }))
            .pipe(rename({ extname: &#39;.min.js&#39; }))
            .pipe(gulp.dest(destinationFolder)) // save .min.js
            .pipe(sourcemaps.write(&#39;maps&#39;))
            .pipe(gulp.dest(destinationFolder)) // save .map
    }


What I am not sure about is the `sourcemaps.init()` location...   

Should I create multiple (2 in my case) map files (that would be nice if is supported by browsers) or only one (*/maps/myModule.map*)?

gulp: uglify and sourcemaps

Currently there are two main popular Java Object to Object mapping frameworks that supersede Dozer (http://dozer.sourceforge.net/documentation/mappings.html), they are: 

 1. Selma - http://www.selma-java.org/
 2. MapStruct - http://mapstruct.org/

With the exception of this page (http://vytas.io/blog/java/java-object-to-object-mapping-which-framework-to-choose-part-2/) I haven&#39;t been able to find much online regarding which framework is better than the other, or under what circumstances they are better. Wondering if anyone you can shed some light on this. In terms of functionality based on the documents, they seem to be doing the same thing.

Content Type	Original Author	Original Content on Stackoverflow
Question	Lucia	View Question on Stackoverflow
Solution 1 - Vim	romainl	View Answer on Stackoverflow
Solution 2 - Vim	Ingo Karkat	View Answer on Stackoverflow
Solution 3 - Vim	Atropo	View Answer on Stackoverflow
Solution 4 - Vim	steffen	View Answer on Stackoverflow
Solution 5 - Vim	Lucia	View Answer on Stackoverflow

What is the meaning of a <CR> at the end of some vim mappings?

Vim Problem Overview

Vim Solutions

Solution 1 - Vim

Solution 2 - Vim

Why `<special keys>`?

Why `<CR>`?

Solution 3 - Vim

Solution 4 - Vim

Solution 5 - Vim

Uncaught TypeError: Cannot read property 'value' of null

AttributeError: 'module' object has no attribute 'request'

Attributions