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List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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Python Script execute commands in Terminal
...nds
s=commands.getstatusoutput('ls')
print s
>> (0, 'file_1\nfile_2\nfile_3')
s[1].split("\n")
>> ['file_1', 'file_2', 'file_3']
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Profiling Vim startup time
... if you want it to just print it, try vim --startuptime /dev/stdout +qall
– Capi Etheriel
Jan 15 '13 at 17:37
1
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C++ Convert string (or char*) to wstring (or wchar_t*)
...f8_source_string);
Longer online compilable and runnable example:
(They all show the same example. There are just many for redundancy...)
http://ideone.com/KA1oty
http://ide.geeksforgeeks.org/5pRLSh
http://rextester.com/DIJZK52174
Note (old):
As pointed out in the comments and explained in h...
How to log PostgreSQL queries?
How to enable logging of all SQL executed by PostgreSQL 8.3?
10 Answers
10
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Getting current device language in iOS?
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The solutions provided will actually return the current region of the device - not the currently selected language. These are often one and the same. However, if I am in North America and I set my language to Japanese, my region will still be English (Unite...
How to access component methods from “outside” in ReactJS?
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class Parent extends React.Class {
constructor(props) {
this._child = React.createRef();
}
componentDidMount() {
console.log(this._child.current.someMethod()); // Prints 'bar'
}
render() {
return (
<div>
<Child ref=...
mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
Can a C# class inherit attributes from its interface?
...h is searched for the attributes.</param>
/// <returns>Returns all attributes.</returns>
public static T[] GetCustomAttributes<T>( this Type type ) where T : Attribute
{
return GetCustomAttributes( type, typeof( T ), false ).Select( arg => (T)arg ).ToArray();
}
/// <...
What does it mean for a data structure to be “intrusive”?
...to know about the list it is in, and inform it of changes.
ORM-systems usually revolve around intrusive data structures, to minimize iteration over large lists of objects. For instance, if you retrieve a list of all the employees in the database, then change the name of one of them, and want to sav...