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How to implement an ordered, default dict? [duplicate]
...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
...
Watch multiple $scope attributes
... new method called $watchGroup for observing a set of expressions.
$scope.foo = 'foo';
$scope.bar = 'bar';
$scope.$watchGroup(['foo', 'bar'], function(newValues, oldValues, scope) {
// newValues array contains the current values of the watch expressions
// with the indexes matching those of th...
A variable modified inside a while loop is not remembered
...
@AvinashYadav The problem isn't really related to while loop or for loop; rather the use of subshell i.e., in cmd1 | cmd2, cmd2 is in a subshell. So if a for loop is executed in a subshell, the unexpected/problematic behaviour will be exhibited.
...
Easiest way to check for an index or a key in an array?
... associative array)
[ ${array[key]+abc} ] && echo "exists"
Basically what ${array[key]+abc} does is
if array[key] is set, return abc
if array[key] is not set, return nothing
References:
See Parameter Expansion in Bash manual and the little note
if the colon is omitted, the ope...
Javascript: best Singleton pattern [duplicate]
... return instance;
}
this.instance = this;
}
foo() {
// ...
}
}
console.log(new Singleton() === new Singleton());
(2) ES6 Version
class Singleton {
constructor() {
const instance = this.constructor.instance;
if (instance) {
...
How can I add reflection to a C++ application?
...rate the data about each field(plus the field itself). This macro will be called like this:
REFLECTABLE
(
(const char *) name,
(int) age
)
So using Boost.PP we iterate over each argument and generate the data like this:
// A helper metafunction for adding const to a type
template<clas...
split string only on first instance - java
... length will be no greater than n, and the array's last entry will contain all input beyond the last matched delimiter.
The string boo:and:foo, for example, yields the following results with these parameters:
Regex Limit Result
: 2 { "boo", "and:foo" }
: 5 { "boo", "an...
What does the explicit keyword mean?
...
The compiler is allowed to make one implicit conversion to resolve the parameters to a function. What this means is that the compiler can use constructors callable with a single parameter to convert from one type to another in order to get t...
What are 'closures' in .NET?
...gate int testDel();
static void Main(string[] args)
{
int foo = 4;
testDel myClosure = delegate()
{
return foo;
};
int bar = myClosure();
}
At the end of it, bar will be set to 4, and the myClosure delegate can be passed around to b...
Defining a variable with or without export
...
Specifically export makes the variable available to child processes via the environment.
– Beano
Jul 21 '09 at 13:35
...