If you really want to create an array rather than a list use either

    String[] names = [&quot;lucas&quot;, &quot;Fred&quot;, &quot;Mary&quot;]

or

    def names = [&quot;lucas&quot;, &quot;Fred&quot;, &quot;Mary&quot;].toArray()




Most of the time you would create a list in groovy rather than an array. You could do it like this:

    names = [&quot;lucas&quot;, &quot;Fred&quot;, &quot;Mary&quot;]

Alternately, if you did not want to quote everything like you did in the ruby example, you could do this:

    names = &quot;lucas Fred Mary&quot;.split()

I can specify an integer literal of type unsigned long as follows:

    const unsigned long example = 9UL;

How do I do likewise for an unsigned char?

    const unsigned char example = 9U?;

This is needed to avoid compiler warning:

    unsigned char example2 = 0;
    ...
    min(9U?, example2);

I&#39;m hoping to avoid the verbose workaround I currently have and not have &#39;unsigned char&#39; appear in the line calling min without declaring 9 in a variable on a separate line:

    min(static_cast&lt;unsigned char&gt;(9), example2);

How do I specify an integer literal of type unsigned char in C++?

I have a `DropDownList` binded with a`SqlDataSource` to display the values from the database.

I am unable to validate using a `RequiredFieldValidator`.

How to add a RequiredFieldValidator to DropDownList control?

In ruby, there is a indiom to create a array of strings like this:

    names = %w( lucas Fred Mary )

Is there something like that in groovy?

Array of strings in groovy

In ruby, there is a indiom to create a array of strings like this:
<pre><code class="hljs language-ini">names = %w( lucas Fred Mary )
</code></pre>
Is there something like that in groovy?

I have an Array `var cars = [2,3,..]` which holds a few integers.
I&#39;ve added a few values to the array, but I now need to send this array to a page via jQuery&#39;s `.get` method. How can I convert it to a JSON object for sending?

Convert array to JSON

I have 2 arrays, the value will be loaded from database, below is an example:

    $arr1 = array(1,2,3);
    $arr2 = array(1,2,3,4,5,6,7);

What I want to do is to check if **all the values** in `$arr1` exist in `$arr2`. The above example should be a `TRUE` while:

    $arr3 = array(1,2,4,5,6,7);

comparing `$arr1` with `$arr3` will return a `FALSE`.

Normally I use `in_array` because I only need to check single value into an array. But in this case, `in_array` cannot be used. I&#39;d like to see if there is a simple way to do the checking with a minimum looping.

UPDATE for clarification.

First array will be a set that contains unique values. Second array can contain duplicated values. They are both guaranteed an array before processing.


How can I use in_array if the needle is an array?

I iterate through an array of objects and want to delete one of the objects based on it&#39;s &#39;id&#39; property, but my code doesn&#39;t work.

    foreach($array as $element) {
        foreach($element as $key =&gt; $value) {
            if($key == &#39;id&#39; &amp;&amp; $value == &#39;searched_value&#39;){
                //delete this particular object from the $array
                unset($element);//this doesn&#39;t work
                unset($array,$element);//neither does this
            } 
        }
    }
Any suggestions. Thanks.

How to delete object from array inside foreach loop?

Is it possible to store all matches for a regular expression into an array?

I know I can use `($1,...,$n) = m/expr/g;`, but it seems as though that can only be used if you know the number of matches you are looking for. I have tried `my @array = m/expr/g;`, but that doesn&#39;t seem to work.



How can I store regex captures in an array in Perl?

Memory access through pointers is said to be more efficient than memory access through an array.  I am learning C and the above is stated in K&amp;R. Specifically they say

&gt; Any operation that can be achieved by array subscripting can also be done with pointers. The pointer version will in general be faster

I dis-assembled the following code using visual C++.(Mine is a 686 processor. I have disabled all optimizations.)

    int a[10], *p = a, temp;

    void foo()
    {
        temp = a[0];
        temp = *p;
    }

To my surprise I see that memory access through a pointer takes 3 instructions to the two taken by memory access through an array. Below is the corresponding code.

    ; 5    : temp = a[0];

    	mov	eax, DWORD PTR _a
    	mov	DWORD PTR _temp, eax
    
    ; 6    : temp = *p;
    
    	mov	eax, DWORD PTR _p
    	mov	ecx, DWORD PTR [eax]
    	mov	DWORD PTR _temp, ecx


Please help me understand. What am I missing here??


----------
As pointed out by many answers and comments I had used a compile time constant as the array index thus making it arguably easier for the access through an array. Below is the assembly code with a variable as the index. I now have equal number of instructions for access through pointer and arrays. My broader questions still holds good. The memory access through a pointer is not lending itself as being more efficient.

    ; 7    : 		temp = a[i];
    
    	mov	eax, DWORD PTR _i
    	mov	ecx, DWORD PTR _a[eax*4]
    	mov	DWORD PTR _temp, ecx
    
    ; 8    : 
    ; 9    : 	
    ; 10   : 		temp = *p;
    
    	mov	eax, DWORD PTR _p
    	mov	ecx, DWORD PTR [eax]
    	mov	DWORD PTR _temp, ecx

Efficiency: arrays vs pointers

I have an enumeration:

    public enum MyColours
    {
        Red,
        Green,
        Blue,
        Yellow,
        Fuchsia,
        Aqua,
        Orange
    }

and I have a string:

    string colour = &quot;Red&quot;;

I want to be able to return:

    MyColours.Red

from:

    public MyColours GetColour(string colour)

------------
So far i have:

    public MyColours GetColours(string colour)
    {
        string[] colours = Enum.GetNames(typeof(MyColours));
        int[]    values  = Enum.GetValues(typeof(MyColours));
        int i;
        for(int i = 0; i &lt; colours.Length; i++)
        {
            if(colour.Equals(colours[i], StringComparison.Ordinal)
                break;
        }
        int value = values[i];
        // I know all the information about the matched enumeration
        // but how do i convert this information into returning a
        // MyColour enumeration?
    }

As you can see, I&#39;m a bit stuck.  Is there anyway to select an enumerator by value.  Something like:

    MyColour(2) 

would result in

    MyColour.Green

Search for a string in Enum and return the Enum

How can I get the position of a character inside a string in Python?

How to get the position of a character in Python?

What is the best way to generate a long string quickly in ruby?  This works, but is very slow:

    str = &quot;&quot;
    length = 100000
    (1..length).each {|i| str += &quot;0&quot;}

I&#39;ve also noticed that creating a string of a decent length and then appending that to an existing string up to the desired length works much faster:

    str = &quot;&quot;
    incrementor = &quot;&quot;
    length = 100000
    (1..1000).each {|i| incrementor += &quot;0&quot;}
    (1..100).each {|i| str += incrementor}

Any other suggestions?

In Ruby how do I generate a long string of repeated text?

In JavaScript this is how we can split a string at every 3-rd character

    &quot;foobarspam&quot;.match(/.{1,3}/g)

I am trying to figure out how to do this in Java. Any pointers?

Splitting a string at every n-th character

I noticed in the Java 6 source code for String that hashCode only caches values other than 0. The difference in performance is exhibited by the following snippet:

    public class Main{
       static void test(String s) {
          long start = System.currentTimeMillis();
          for (int i = 0; i &lt; 10000000; i++) {
             s.hashCode();
          }
          System.out.format(&quot;Took %d ms.%n&quot;, System.currentTimeMillis() - start);
       }
       public static void main(String[] args) {
          String z = &quot;Allocator redistricts; strict allocator redistricts strictly.&quot;;
          test(z);
          test(z.toUpperCase());
       }
    }

&lt;a href=&quot;https://web.archive.org/web/20000000000000/http://www.ideone.com/Ho9lfOKy&quot;&gt;Running this in ideone.com&lt;/a&gt; gives the following output:

    Took 1470 ms.
    Took 58 ms.

So my questions are:

 * Why doesn&#39;t String&#39;s hashCode() cache 0?
 * What is the probability that a Java string hashes to 0?
 * What&#39;s the best way to avoid the performance penalty of recomputing the hash value every time for strings that hash to 0?
 * Is this the best-practice way of caching values? (i.e. cache all except one?)

----

For your amusement, each line here is a string that hash to 0:

    pollinating sandboxes
    amusement &amp; hemophilias
    schoolworks = perversive
    electrolysissweeteners.net
    constitutionalunstableness.net
    grinnerslaphappier.org
    BLEACHINGFEMININELY.NET
    WWW.BUMRACEGOERS.ORG
    WWW.RACCOONPRUDENTIALS.NET
    Microcomputers: the unredeemed lollipop...
    Incentively, my dear, I don&#39;t tessellate a derangement.
    A person who never yodelled an apology, never preened vocalizing transsexuals.

Why doesn&#39;t String&#39;s hashCode() cache 0?

Is it possible to `break` from a Groovy `.each{Closure}`, or should I be using a classic loop instead?

Can you break from a Groovy &quot;each&quot; closure?

What is the best way to remove null items from a list in Groovy?

ex: `[null, 30, null]`

want to return: `[30]`

Remove null items from a list in Groovy

I am coding this with Groovy 

I am currently trying to convert a string that I have to a date without having to do anything too tedious. 

    String theDate = &quot;28/09/2010 16:02:43&quot;;
    def newdate = new Date().parse(&quot;d/M/yyyy H:m:s&quot;, theDate)


Output: 

    Tue Aug 10 16:02:43 PST 2010


The above code works just fine, however when my string changes to something like:

    String testDate = &quot;Tue Aug 10 16:02:43 PST 2010&quot;
    def newerdate = new Date().parse(&quot;d/M/yyyy H:m:s&quot;, testDate)

It tells me that &quot;there is no such value for Tue&quot;. I tried to throw an &#39;E&#39; in the parse for the date but it said the date was not able to be parsed.

Can someone explain how I should go about parsing the second example?
     

Groovy String to Date

I&#39;m trying to get (not print, that&#39;s easy) the list of files in a directory and its sub directories.

I&#39;ve tried:

    def folder = &quot;C:\\DevEnv\\Projects\\Generic&quot;;
    def baseDir = new File(folder);
    files = baseDir.listFiles();

I only get the directories. I&#39;ve also tried:

    def files = [];

    def processFileClosure = {
            println &quot;working on ${it.canonicalPath}: &quot;
            files.add (it.canonicalPath);
        }

    baseDir.eachFileRecurse(FileType.FILES, processFileClosure);

But &quot;files&quot; is not recognized in the scope of the closure.

How do I get the list?



Get a list of all the files in a directory (recursive)

Is there a `map` method in Groovy? I want to do something like I do with the following Scala snippet:

    scala&gt; val l = List(1, 2, 3)
    l: List[Int] = List(1, 2, 3)
    
    scala&gt; l.map(_ + 1)
    res0: List[Int] = List(2, 3, 4)

Content Type	Original Author	Original Content on Stackoverflow
Question	Lucas	View Question on Stackoverflow
Solution 1 - Arrays	Dónal	View Answer on Stackoverflow
Solution 2 - Arrays	Chris Dail	View Answer on Stackoverflow

Array of strings in groovy

Arrays Problem Overview

Arrays Solutions

Solution 1 - Arrays

Solution 2 - Arrays

How to add a RequiredFieldValidator to DropDownList control?

How do I specify an integer literal of type unsigned char in C++?

Attributions