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Why can I change value of a constant in javascript
...se I thought that idea of the constant is that it can not be changed. Basically a programmer has trust that no matter what will happen, nothing can change the value inside of my constant.
– Salvador Dali
May 2 '14 at 20:39
...
What is the difference between self-types and trait subclasses?
...is extended, then you're required to mix-in an A.
When a concrete class finally extends/mixes-in these traits, some class/trait must implement A.
Consider the following examples:
scala> trait User { def name: String }
defined trait User
scala> trait Tweeter {
| user: User =>
...
Why is list initialization (using curly braces) better than the alternatives?
...
Basically copying and pasting from Bjarne Stroustrup's "The C++ Programming Language 4th Edition":
List initialization does not allow narrowing (§iso.8.5.4). That is:
An integer cannot be converted to another integer that cann...
JavaScript isset() equivalent
...
I generally use the typeof operator:
if (typeof obj.foo !== 'undefined') {
// your code here
}
It will return "undefined" either if the property doesn't exist or its value is undefined.
(See also: Difference between undefi...
How to use a filter in a controller?
...Prashanth is correct, but there is even easier way of doing the same. Basically instead of injecting the $filter dependency and using awkward syntax of invoking it ($filter('filtername')(arg1,arg2);) one can inject dependency being: filter name plus the Filter suffix.
Taking example from the quest...
Convert interface{} to int
...e type conversion, look at the code below:
package main
import "fmt"
func foo(a interface{}) {
fmt.Println(a.(int)) // conversion of interface into int
}
func main() {
var a int = 10
foo(a)
}
This code executes perfectly and converts interface type to int type
For an expression x...
How to install gem from GitHub source?
I would like to install gem from the latest GitHub source.
11 Answers
11
...
What can , and be used for?
...iewParam name="id" value="#{bean.id}" />
</f:metadata>
does basically the following:
Get the request parameter value by name id.
Convert and validate it if necessary (you can use required, validator and converter attributes and nest a <f:converter> and <f:validator> in it like...
Declare a block method parameter without using a typedef
...ally be preferred for more complicated cases.
– Fred Foo
Mar 30 '11 at 13:35
3
- ( void )myMethod...
What is move semantics?
...regarding C++0x . Most of the new features made sense to me, and I am actually excited about C++0x now, with the exception of one. I still don't get move semantics ... What is it exactly?
...