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Static class initializer in PHP
...nswers (including this one), I prefer Victor Nicollet's answer. Simple. No extra coding required. No "advanced" coding to understand. (I recommend including FrancescoMM's comment, to make sure "init" will never execute twice.)
So I could have not bothered to write this answer. But so many people up...
bash assign default value
...riable without needing to reassign
# colons suppress attempting to run the string
unset EGGS
: ${EGGS=spam}
echo 1 $EGGS # 1 spam
unset EGGS
: ${EGGS:=spam}
echo 2 $EGGS # 2 spam
EGGS=
: ${EGGS=spam}
echo 3 $EGGS # 3 (set, but blank -> leaves alone)
EGGS=
: ${EGGS:=spam}
echo ...
When is each sorting algorithm used? [closed]
...rantee no bad data gives you O(N^2), you should avoid it.
Merge-sort uses extra memory, but is particularly suitable for external sorting (i.e. huge files that don't fit into memory).
Heap-sort can sort in-place and doesn't have the worst case quadratic behavior, but on average is slower than quic...
How does #include work in C++? [duplicate]
... words it's perfectly legal for an implementation to declare the name std::string directly or indirectly when using #include <vector>).
Despite this however you are required by the language to know and tell the compiler which standard header includes which part of the standard library. This i...
Get all unique values in a JavaScript array (remove duplicates)
...ust be a duplicate and will not be copied.
This solution works without any extra library like jQuery or prototype.js.
It works for arrays with mixed value types too.
For old Browsers (<ie9), that do not support the native methods filter and indexOf you can find work arounds in the MDN documentati...
What is the best way to concatenate two vectors?
...erator>
#include <iostream>
#include <sstream>
#include <string>
template<template<typename, typename...> class Container, class T>
std::string toString(const Container<T>& v)
{
std::stringstream ss;
std::copy(v.begin(), v.end(), std::ostream_itera...
Why is it impossible to override a getter-only property and add a setter? [closed]
...or the purpose of serialization.
interface ITest
{
// Other stuff
string Prop { get; }
}
// Implements other stuff
abstract class ATest : ITest
{
abstract public string Prop { get; }
}
// This implementation of ITest needs the user to set the value of Prop
class BTest : ATest
{
st...
How to enable/disable bluetooth programmatically in android
...
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (action.equals(BluetoothAdapter.ACTION_STATE_CHANGED)) {
final int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE,
...
How to remove old Docker containers
...optionally, volumes, in one command.
For older Docker versions, you can string Docker commands together with other Unix commands to get what you need. Here is an example on how to clean up old containers that are weeks old:
$ docker ps --filter "status=exited" | grep 'weeks ago' | awk '{print $1...
How to find a table having a specific column in postgresql
...
Wildcard Support
Find the table schema and table name that contains the string you want to find.
select t.table_schema,
t.table_name
from information_schema.tables t
inner join information_schema.columns c on c.table_name = t.table_name
and c.table_schema =...