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What does new self(); mean in PHP?

...etInstance method is in a class name MyClass, the following line : self::$_instance = new self(); Will do the same as : self::$_instance = new MyClass(); Edit : a couple more informations, after the comments. If you have two classes that extend each other, you have two situations : get...
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Installing older version of R package

...ageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz" install.packages(packageurl, repos=NULL, type="source") If this doesn't work for you and you're on Windows, the reason is probably the lack of an appropriate tool chain for building/compiling packages. Normal...
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Where are $_SESSION variables stored?

Are $_SESSION variables stored on the client or the server? 11 Answers 11 ...
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SQLAlchemy: print the actual query

...itting DDL. In order to access this functionality one can use the 'literal_binds' flag, passed to compile_kwargs: from sqlalchemy.sql import table, column, select t = table('t', column('x')) s = select([t]).where(t.c.x == 5) print(s.compile(compile_kwargs={"literal_binds": True})) the above app...
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Remove last item from array

... learn by example: let array_1 = [1,2,3,4]; let array_2 = [1,2,3,4]; let array_3 = [1,2,3,4]; array_1.splice(-1,1) // output --> [4] array_1 = [1,2,3] array_2.slice(0,-1); // output --> [1,2,3] array_2 = [1,2,3,4] array_3.pop(); //...
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What is the volatile keyword useful for?

... volatile: public class Singleton { private static volatile Singleton _instance; // volatile variable public static Singleton getInstance() { if (_instance == null) { synchronized (Singleton.class) { if (_instance == null) _instance = ...
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How to apply bindValue method in LIMIT clause?

...I think this solves it. $fetchPictures->bindValue(':skip', (int) trim($_GET['skip']), PDO::PARAM_INT); share | improve this answer | follow | ...
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Replacing spaces with underscores in JavaScript?

I'm trying to use this code to replace spaces with _, it works for the first space in the string but all the other instances of spaces remain unchanged. Anybody know why? ...
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How to set child process' environment variable in Makefile

...ever you can use make's export to force them to do so. Change: test: NODE_ENV = test to this: test: export NODE_ENV = test (assuming you have a sufficiently modern version of GNU make >= 3.77 ). share | ...
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Using mixins vs components for code reuse in Facebook React

...nding fields. Source (gist) define(function () { 'use strict'; var _ = require('underscore'); var ValidationMixin = { getInitialState: function () { return { errors: [] }; }, componentWillMount: function () { this.assertValidatorsDefined(); }, ...