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PHP check whether property exists in object or class
...y_exists($ob, 'a'))
isset( mixed $var [, mixed $... ] )
if (isset($ob->a))
isset() will return false if property is null
Example 1:
$ob->a = null
var_dump(isset($ob->a)); // false
Example 2:
class Foo
{
public $bar = null;
}
$foo = new Foo();
var_dump(property_exists($f...
Visual Studio loading symbols
...
Debug -> Delete All Breakpoints ( http://darrinbishop.com/blog/2010/06/sharepoint-2010-hangs-after-visual-studio-2010-f5-debugging )
After that you can use them again, but do it once. It will remove some kind of "invalid" breakpoi...
Cleaner way to update nested structures
...ippers for annotated case classes. I'll reproduce his example here:
scala> @zip case class Pacman(lives: Int = 3, superMode: Boolean = false)
scala> @zip case class Game(state: String = "pause", pacman: Pacman = Pacman())
scala> val g = Game()
g: Game = Game("pause",Pacman(3,false))
//...
Coffeescript — How to create a self-initiating anonymous function?
...
While you can just use parentheses (e.g. (-> foo)(), you can avoid them by using the do keyword:
do f = -> console.log 'this runs right away'
The most common use of do is capturing variables in a loop. For instance,
for x in [1..3]
do (x) ->
setTimeo...
Eclipse: have the same file open in two editors?
...
Open your file and then Window->New Editor (Note: in newer versions it will be called New Window)
Then, click on its tab and drag it somewhere else to have two editors of the same file
Update: as mentioned by moschlar, From version 4.4, two editors can...
passing several arguments to FUN of lapply (and others *apply)
I have a question regarding passing multiple arguments to a function, when using lapply in R .
4 Answers
...
Why are Python lambdas useful? [closed]
...way to write something out.
Returning a function from another function
>>> def transform(n):
... return lambda x: x + n
...
>>> f = transform(3)
>>> f(4)
7
This is often used to create function wrappers, such as Python's decorators.
Combining elements of an iterab...
What exactly does += do in python?
...addition of itself plus the other number which makes sense in this case.
>>> class Adder(object):
def __init__(self, num=0):
self.num = num
def __iadd__(self, other):
print 'in __iadd__', other
self.num = self.num + other
ret...
How are “mvn clean package” and “mvn clean install” different?
...er, before executing the command itself.
order of execution
validate >> compile >> test (optional) >> package >> verify >> install >> deploy
So when you run the command mvn package, it runs the commands for all lifecycle phases till package
validate >...
config.assets.compile=true in Rails production, why not?
The default Rails app installed by rails new has config.assets.compile = false in production.
7 Answers
...