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What is the point of interfaces in PHP?
...e. Most of the problems with multiple inheritance don't apply to abstract base classes, so most modern languages these days disable multiple inheritance yet call abstract base classes interfaces and allows a class to "implement" as many of those as they want.
...
Case in Select Statement
...earched CASE expression allows for values to be replaced in the result set based on comparison values. The following example displays the list price as a text comment based on the price range for a product.
USE AdventureWorks2012;
GO
SELECT ProductNumber, Name, "Price Range" =
CASE
...
`static` keyword inside function?
... static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In this example, the if would only be executed once. Even if multiple calls to doStuff would occur.
...
Paperclip::Errors::MissingRequiredValidatorError with Rails 4
...s_attachment_content_type in Model
Rails 3
class User < ActiveRecord::Base
attr_accessible :avatar
has_attached_file :avatar, :styles => { :medium => "300x300>", :thumb => "100x100>" }, :default_url => "/images/:style/missing.png"
validates_attachment_content_type :avatar, :co...
belongs_to through associations
...
You can also delegate:
class Company < ActiveRecord::Base
has_many :employees
has_many :dogs, :through => :employees
end
class Employee < ActiveRescord::Base
belongs_to :company
has_many :dogs
end
class Dog < ActiveRecord::Base
belongs_to :employee
deleg...
Load dimension value from res/values/dimension.xml from source code
...etrieve a dimensional for a particular resource ID. Unit conversions
are based on the current DisplayMetrics associated with the resources.
so if you want exact dp value just as in xml just divide it with DisplayMetrics density
int dp = (int) (getResources().getDimension(R.dimen.test) / getReso...
Design Patterns: Abstract Factory vs Factory Method
...oduct. (It is better than the Static Factory. When new types are added the base Product class does not need to be changed only the Simple Factory Class)
Factory Method
Contains one method to produce one type of product related to its type. (It is better than a Simple Factory because the type is ...
Java8: Why is it forbidden to define a default method for a method from java.lang.Object
...single Displayable to implement toString() or extend a DisplayableToString base class.
– Brandon
Jun 10 '14 at 22:07
...
convert an enum to another type of enum
...then cast it to the other enum (considering that you want the mapping done based on value):
Gender2 gender2 = (Gender2)((int)gender1);
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Find a file in python
...leAttributesW(unicode(path)) & FILE_ATTRIBUTE_REPARSE_POINT)
def find(base, filenames):
hits = []
def find_in_dir_subdir(direc):
content = scandir(direc)
for entry in content:
if entry.name in filenames:
hits.append(os.path.join(direc, entry....