You can wrap values into actions and pipe the result of one computation into another:
return :: Monad m => a -> m a
(>>=) :: Monad m => m a -> (a -> m b) -> m b
However, the definition of a Monad doesn’t guarantee the existence of a function of type Monad m => m a -&...
CoffeeScript allows to deconstruct objects and arrays when they are fed to functions as arguments.
A function that leverages deconstruction will specify in its signature all the fields that are expected within its body. When invoking such function, an object or array containing all the expected fie...
Enums are defined by the following the syntax above.
typedef NS_ENUM(NSUInteger, MyEnum) {
MyEnumValueA,
MyEnumValueB,
MyEnumValueC,
};
You also can set your own raw-values to the enumeration types.
typedef NS_ENUM(NSUInteger, MyEnum) {
MyEnumValueA = 0,
MyEnumValueB =...
When object's are linked by a lookup or master-detail relationship, the parent records field's can be referenced from the child record or 'base object' in a query. This is also known as upwards traversal.
SELECT FirstName, Account.Name, Account.Category__c FROM Contact
It's possible to traverse ...
Any public Sub, Function, or Property inside a class module can be called by preceding the call with an object reference:
Object.Procedure
In a DateRange class, a Sub could be used to add a number of days to the end date:
Public Sub AddDays(ByVal NoDays As Integer)
mEndDate = mEndDate + No...
Another useful feature is accessing your custom object collections as arrays in PHP. There are two interfaces available in PHP (>=5.0.0) core to support this: ArrayAccess and Iterator. The former allows you to access your custom objects as array.
ArrayAccess
Assume we have a user class and a da...
You can register for notifications of when the device text size is changed.
Swift
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(updateFont), name: name:UIContentSizeCategoryDidChangeNotification, object: nil)
Objective-C
[[NSNotificationCenter defaultCenter] addObs...
There are 3 main ways to fetch results from a query:
sqlsrv_fetch_array()
sqlsrv_fetch_array() retrieves the next row as an array.
$stmt = sqlsrv_query($conn, $query);
while($row = sqlsrv_fetch_array($stmt)) {
echo $row[0];
$var = $row["name"];
//...
}
sqlsrv_fetch...
Create this class :
public class InputFilterMinMax implements InputFilter {
private int min, max;
public InputFilterMinMax(int min, int max) {
this.min = min;
this.max = max;
}
public InputFilterMinMax(String min, String max) {
this.min = Integer...
When first introduced, AsyncTasks were executed serially on a single background thread. Starting with DONUT, this was changed to a pool of threads allowing multiple tasks to operate in parallel. Starting with HONEYCOMB, tasks are executed on a single thread to avoid common application errors caused ...
The CharField is used for storing defined lengths of text. In the example below up to 128 characters of text can be stored in the field. Entering a string longer than this will result in a validation error being raised.
from django.db import models
class MyModel(models.Model):
name = models...
The unsafe keyword can be used in type or method declarations or to declare an inline block.
The purpose of this keyword is to enable the use of the unsafe subset of C# for the block in question. The unsafe subset includes features like pointers, stack allocation, C-like arrays, and so on.
Unsafe ...
You can use the following code for going back and forward.
if (!function_exists('codepoint_encode')) {
function codepoint_encode($str) {
return substr(json_encode($str), 1, -1);
}
}
if (!function_exists('codepoint_decode')) {
function codepoint_decode($str) {
re...
When localizing different types of resources are required, each of which has its own home in the android project structure.
Following are the different directories that we can place under the \res directory. The resource types placed in each of these directories are explained in the table below:
D...
Each resource directory under the res folder (listed in the example above) can have different variations of the contained resources in similarly named directory suffixed with different qualifier-values for each configuration-type.
Example of variations of `` directory with different qualifier value...
C and C++ are well known as high-performance languages - largely due to the heavy amount of code customization, allowing a user to specify performance by choice of structure.
When optimizing it is important to benchmark relevant code and completely understand how the code will be used.
Common opti...
