Whatever works best for you works...
But if you want to go for speed use this:

    echo &#39;Welcome &#39;, $name, &#39;!&#39;;

The single quotes tell PHP that no interpretation is needed, and the comma tells PHP to just echo the string, no concatenation needed.

I have the following requirement:

 - At first, data for page no: 2 is fetched from the server &amp; the items
   are populated in a ListView.

Considering that both the prev page &amp; next page are available in a scenario, the following code has been added:

     if(prevPageNo &gt; 0){
        mListViewActual.setOnScrollListener(this);
     }
        
     if(nextPageNo &gt; 0){
        mListViewActual.setOnScrollListener(this);
     }


What conditions should I put to detect scroll up &amp; scroll down on the following methods:

 1. void onScroll(AbsListView view, int firstVisibleItem, int
    visibleItemCount, int totalItemCount)
 2. void onScrollStateChanged(AbsListView view, int scrollState)

After the action: scroll up &amp; scroll down is detected , accordingly a service will be called with either the prev page no or next page no , to fetch the items to be populated in the Listview.

Any inputs will be helpful.

Gone through the following links but its not returning the correct scroll up / scroll down action:

[link 1][1]
[link 2][2]

  [1]: https://stackoverflow.com/questions/9629872/how-to-detect-if-a-listview-is-scrolling-up-or-down-in-android
  [2]: https://stackoverflow.com/questions/12114963/detecting-the-scrolling-direction-in-the-adapter-up-down

Detect Scroll Up &amp; Scroll down in ListView

I have quite a simple problem to solve. I have Partner model which has &gt;= 0 Users associated with it:

    class Partner(models.Model):
        name = models.CharField(db_index=True, max_length=255)
        slug = models.SlugField(db_index=True)
        user = models.ManyToManyField(User)


Now, if I have a User object and I have a Partner object, what is the most Pythonic way of checking if the User is associated with a Partner? I basically want a statement which returns True if the `User` is associated to the `Partner`. 

I have tried:

    users = Partner.objects.values_list(&#39;user&#39;, flat=True).filter(slug=requested_slug)
    if request.user.pk in users:
        # do some private stuff

This works but I have a feeling there is a better way. Additionally, would this be easy to roll into a decorator, baring in mind I need both a named parameter (`slug`) and a request object (`user`).


Django check if object in ManyToMany field

What is the difference between the two following methods (performance, readability, etc.) and what do you prefer?

    echo &quot;Welcome {$name}s!&quot;

vs.

    echo &quot;Welcome &quot; . $name . &quot;!&quot;;


PHP variable interpolation vs concatenation

What is the difference between the two following methods (performance, readability, etc.) and what do you prefer?
<pre><code class="hljs language-bash">echo "Welcome {$name}s!"
</code></pre>
vs.
<pre><code class="hljs language-bash">echo "Welcome " . $name . "!";
</code></pre>

I can&#39;t figure out how to add a new column to my existing database table using the Laravel framework.

I tried to edit the migration file using...

&lt;!-- language: php --&gt;

    &lt;?php
    
    public function up()
    {
        Schema::create(&#39;users&#39;, function ($table) {
            $table-&gt;integer(&quot;paid&quot;);
        });
    }

In terminal, I execute `php artisan migrate:install` and `migrate`.

How do I add new columns?

Laravel Add a new column to existing table in a migration

I want to get the id of the session in Laravel 4

In Laravel 3, it was a bit hacky, but possible with this code:

    $session_id = Session::$instance-&gt;session[&#39;id&#39;];

But I can&#39;t work it out in Laravel 4... referencing the `Session::$instance` object throws errors: 

&gt; Access to undeclared static property: Illuminate\Support\Facades\Session::$instance

have tried:

    $session_id = Session::get(&#39;id&#39;);

but to no avail.. any ideas?

How can I get the session ID in Laravel?

How can I make this query in Laravel:

    SELECT 
    	`p`.`id`,
    	`p`.`name`, 
    	`p`.`img`, 
    	`p`.`safe_name`, 
    	`p`.`sku`, 
    	`p`.`productstatusid` 
    FROM `products` p 
    WHERE `p`.`id` IN (
    	SELECT 
    		`product_id` 
    	FROM `product_category`
        WHERE `category_id` IN (&#39;223&#39;, &#39;15&#39;)
    )
    AND `p`.`active`=1

I could also do this with a join, but I need this format for performance.

How to do this in Laravel, subquery where in

I am trying to use the `migrate` function in Laravel 4 on OSX. However, I am getting the following error:

    Laravel requires the Mcrypt PHP extension.

As far as I understand, it&#39;s already enabled (see the image below).

What is wrong, and how can I fix it?

![enter image description here][1]


  [1]: http://i.stack.imgur.com/ezq8a.png

Laravel requires the Mcrypt PHP extension

I need to check if a variable is an object of the User type.
User is my class `$user` my object

    $this-&gt;assertInstanceOf($user,User);

This is not working, I have a use of undefined constant User - assumed &#39;User&#39;



Thanks in advance for your help

PHPUnit: assertInstanceOf() not working

In JavaScript, I can declare a string in the following ways;

    var a = &quot;Hello World&quot;;
    var b = new String(&quot;Hello World&quot;);

but a is not an instance of String...

    console.log(a instanceof String); //false;
    console.log(b instanceof String); //true;

So how do you find the type or &quot;`instanceof`&quot; a string literal?

Can JavaScript be forced to create a `new String()` for every string literal?

How to &quot;instanceof&quot; a primitive string (string literal) in JavaScript

I need to declare an empty string array and i&#39;m using this code

    string[] arr = new String[0]();

But I get &quot;method name expected&quot; error.

What&#39;s wrong?

C# declare empty string array

How can I create a [`java.nio.file.Path`][1] object from a `String` object in Java 7?

I.e.

    String textPath = &quot;c:/dir1/dir2/dir3&quot;;
    Path path = ?;

where `?` is the missing code that uses `textPath`.

  [1]: http://docs.oracle.com/javase/7/docs/api/java/nio/file/Path.html

Create a Path from String in Java7

I have this text file made up of numbers and words, for example like this - `09807754 18 n 03 aristocrat 0 blue_blood 0 patrician` and I want to split it so that each word or number will come up as a new line. 

A whitespace separator would be ideal as I would like the words with the dashes to stay connected.

This is what I have so far: 

    f = open(&#39;words.txt&#39;, &#39;r&#39;)
    for word in f:
        print(word)

not really sure how to go from here, I would like this to be the output:

    09807754
    18
    n
    3
    aristocrat
    ...


Reading a text file and splitting it into single words in python

When terminating a string, it seems to me that logically `char c=0` is equivalent to `char c=&#39;\0&#39;`, since the &quot;null&quot; (ASCII 0) byte is `0`, but usually people tend to do `&#39;\0&#39;` instead. Is this purely out of preference or should it be a better &quot;practice&quot;?

What is the preferred choice?

------------

**EDIT:** ***K&amp;R*** *says*: &quot;The character constant `&#39;\0&#39;` represents the character with value zero, the null character. `&#39;\0&#39;` is often written instead of `0` to emphasize the character nature of some expression, but the numeric value is just `0`.

String termination - char c=0 vs char c=&#39;\0&#39;

I have some problem using ajax.

How can I assign all result from ajax into outside variable ?

I google it up and found this code..

    var return_first = (function () {
    	var tmp = null;
    	$.ajax({
    		&#39;async&#39;: false,
    		&#39;type&#39;: &quot;POST&quot;,
    		&#39;global&#39;: false,
    		&#39;dataType&#39;: &#39;html&#39;,
    		&#39;url&#39;: &quot;ajax.php?first&quot;,
    		&#39;data&#39;: { &#39;request&#39;: &quot;&quot;, &#39;target&#39;: arrange_url, &#39;method&#39;: method_target },
    		&#39;success&#39;: function (data) {
    			tmp = data;
    		}
    	});
    	return tmp;
    });

but not work for me..

Can anybody tell what is wrong about that code ?


jQuery return ajax result into outside variable

I have a function that takes the argument `NBins`. I want to make a call to this function with a scalar `50` or an array `[0, 10, 20, 30]`. How can I identify within the function, what the length of `NBins` is? or said differently, if it is a scalar or a vector? 

I tried this:

    &gt;&gt;&gt; N=[2,3,5]
    &gt;&gt;&gt; P = 5
    &gt;&gt;&gt; len(N)
    3
    &gt;&gt;&gt; len(P)
    Traceback (most recent call last):
      File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;
    TypeError: object of type &#39;int&#39; has no len()
    &gt;&gt;&gt; 

As you see, I can&#39;t apply `len` to `P`, since it&#39;s not an array.... Is there something like `isarray` or `isscalar` in python?

thanks

python: how to identify if a variable is an array or a scalar

I need to remove an element from an array in bash shell.
Generally I&#39;d simply do:

    array=(&quot;${(@)array:#&lt;element to remove&gt;}&quot;)

Unfortunately the element I want to remove is a variable so I can&#39;t use the previous command.
Down here an example:

    array+=(pluto)
    array+=(pippo)
    delete=(pluto)
    array( ${array[@]/$delete} ) -&gt; but clearly doesn&#39;t work because of {}

Any idea?

Remove an element from a Bash array

Is there a shorter way of writing something like this:
&lt;!-- language-all: lang-cs --&gt;

    if(x==1 || x==2 || x==3) // do something

What I&#39;m looking for is something like this:

    if(x.in((1,2,3)) // do something

Check if a variable is in an ad-hoc list of values

i have a object, which is getting passed in many different functions inside a function. these functions may or may not change the value of the object, but if they do change it, then i would like to get the latest changes on object.

following is what im trying to do:

    var ob = {text: &#39;this is me&#39;, name: &#39;john&#39;}
    
    function (object) {
    
         changeObject(object);
         customObjectChanger(object);
         callback = function (object) {
              object.text = &#39;new text&#39;;
         }
         
         callback(object);
    
         // object value here should be object{text: &#39;new text&#39;, name: &#39;john&#39;};    
    }

javascript pass object as reference

I was playing with python and I realized we don&#39;t need to use &#39;+&#39; operator to concatenate static strings. But it fails if I assign it to a variable. 

For example:

    string1 = &#39;Hello&#39;   &#39;World&#39;  #1 works fine
    string2 = &#39;Hello&#39; + &#39;World&#39;  #2 also works fine
    
    string3 = &#39;Hello&#39;
    string4 = &#39;World&#39;
    string5 = string3   string4  #3 causes syntax error
    string6 = string3 + string4  #4 works fine

Now I have two questions:

1. Why statement 3 does not work while statement 1 does? 
2. Is there any technical difference such as calculation speed etc. between statement 1 and 2?


String concatenation without &#39;+&#39; operator

We always came across many situation on daily basis wherein we have to do tedious and very many string operations in our code. We all know that string manipulations are expensive operations. I would like to know which is the least expensive among the available versions. 

The most common operations is concatenation(This is something that we can control to some extent). What is the best way to concatenate std::strings in C++  and various workarounds to speed up concatenation?

I mean,

    std::string l_czTempStr;
    
    1).l_czTempStr = &quot;Test data1&quot; + &quot;Test data2&quot; + &quot;Test data3&quot;;
    
    2). l_czTempStr =  &quot;Test data1&quot;; 
        l_czTempStr += &quot;Test data2&quot;;
        l_czTempStr += &quot;Test data3&quot;;
    
    3). using &lt;&lt; operator
    
    4). using append()

Also, do we get any advantage of using CString over std::string?


Most optimized way of concatenation in strings

I have the need to concatenate a string with a field value in a MySQL query in order to LEFT JOIN two tables.

Table one has a column called &quot;category_id&quot; with numeric values, such as 61, 78, 94 and such.

Table two has a column called &quot;query&quot; which refers to a request route mechanism, and it has values such as &quot;product_id=68&quot;, &quot;category_id=74&quot;, &quot;manufacturer_id=99&quot; and so on.

So in my query I require to join the tables when ever a concatenated string derived from a set string and the value of the &quot;category_id&quot; column matches the query field.

My SQL statement is currently:

    SELECT * FROM tableOne 
    LEFT JOIN tableTwo
    ON tableTwo.query = &#39;category_id=&#39; + tableOne.category_id

I have tried using the || operator instead of the + operator, but still no luck. Is it possible to do this in MySQL, or have I jumped the gun here?

Concatenate string with field value in MySQL

What&#39;s the difference between concat, uglify, and minify tasks in grunt? I set up an uglify task for all of my site&#39;s javascript tasks, and it seemed to both minify and concatenate them. Grunt&#39;s site has a great description for how to configure each task, but it doesn&#39;t seem to explain what each task actually does.

What&#39;s the difference between concat and uglify and minify?

I have two string columns `a` and `b` in a table `foo`.

`select a, b from foo` returns values `a` and `b`.  However, concatenation of `a` and `b` does not work. I tried :

    select a || b from foo

and

    select  a||&#39;, &#39;||b from foo

Update from comments: both columns are type `character(2)`.

How to concatenate columns in a Postgres SELECT?

How do I escape a dollar sign in string interpolation?

    def getCompanion(name: String) = Class.forName(s&quot;my.package.$name\$&quot;)
    
    // --&gt; &quot;error: unclosed string literal&quot;

Escape a dollar sign in string interpolation

In Ruby I could do this.

    aaa = &quot;AAA&quot;
    bbb = &quot;BBB #{aaa}&quot;

    puts(bbb)
    
    &gt; &quot;BBB AAA&quot;

The point of this syntax is eliminating repetition, and making it to feel like a shell script - great for heavy string manipulation.

Does Rust support this? Or have plan to support this? Or have some feature which can mimic this?

Does Rust support Ruby-like string interpolation?

Scala has triple quoted strings `&quot;&quot;&quot;String\nString&quot;&quot;&quot;` to use special characters in the string without escaping. Scala 2.10 also added `raw&quot;String\nString&quot;` for the same purpose.

Is there any difference in how `raw&quot;&quot;` and `&quot;&quot;&quot;&quot;&quot;&quot;` work? Can they produce different output for the same string?

What&#39;s the difference between raw string interpolation and triple quotes in scala

String interpolation in C#6 lets me write:

    decimal m = 42.0m;
    string x = $&quot;The value is {m}&quot;;

However, a very common use case for string formatting is to specify the locale used for formatting the values. Let&#39;s say I need to use `InvariantCulture` for the formatting operation above, what is the syntax for that ? 

[This discussion][1] suggests that I should be able to do this:
    
    string x = INV($&quot;The value is {m}&quot;);

Where INV is defined as

    public static string INV(IFormattable formattable)
    {
        return formattable.ToString(null, System.Globalization.CultureInfo.InvariantCulture);
    }

However, this does not work. It compiles, but it leaves my program hanging at in cmd.exe at startup - as if klr.exe, that I assume is being invoked, hangs (Compiler bug?)

This is an ASP.NET 5 Console Project in VS15 CTP 6.

  [1]: https://roslyn.codeplex.com/discussions/570292

Specifying locale for string interpolation in C#6 (Roslyn CTP6)

I&#39;ve been using string interpolation and love it. However, I have an issue where I am trying to include a backslash in my output, but I am not able to get it to work.

I want something like this...

    var domain = &quot;mydomain&quot;;
    var userName = &quot;myUserName&quot;;
    var combo = $&quot;{domain}\{userName}&quot;

I want the output of *combo* to be:

    myDomain\myUserName

I get a syntax error about the \ being an escape character. If I put in \\\ then the syntax error is gone, but the output is *myDomain\\\myUsername*.

How can I include escaped characters in an interpolated string?






Content Type	Original Author	Original Content on Stackoverflow
Question	Aley	View Question on Stackoverflow
Solution 1 - Php	Borniet	View Answer on Stackoverflow

PHP variable interpolation vs concatenation

Php Problem Overview

Php Solutions

Solution 1 - Php

Django check if object in ManyToMany field

Detect Scroll Up & Scroll down in ListView

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