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A simple context tree (containing some common values that might be request scoped and included in a context) built from Go code like the following: // Pseudo-Go ctx := context.WithValue( context.WithDeadline( context.WithValue(context.Background(), sidKey, sid), time.Now().A...

Matplotlib supports both object-oriented and imperative syntax for plotting. The imperative syntax is intentionally designed to be very close to Matlab syntax. The imperative syntax (sometimes called 'state-machine' syntax) issues a string of commands all of which act on the most recent figure or a...

Directives, as the name suggests, are direction or instructions for the container to follow when translating a JSP to a servlet. There are 3 directives namely page, include and taglib which you can use in your JSP. Below is a simple example of using page directive: <%@ page isErrorPage="tr...

To change MySQL's root user password: Step 1: Stop the MySQL server. in Ubuntu or Debian: sudo /etc/init.d/mysql stop in CentOS, Fedora or Red Hat Enterprise Linux: sudo /etc/init.d/mysqld stop Step 2: Start the MySQL server without the privilege system. sudo mysqld_safe --skip-grant-tab...

<?xml version="1.0" encoding="utf-8" ?> <Employees> <Employee> <EmpId>1</EmpId> <Name>Sam</Name> <Sex>Male</Sex> <Phone Type="Home">423-555-0124</Phone> <Phone Type="Work&quot...

To convert decimal number to binary format use base 2 Int32 Number = 15; Console.WriteLine(Convert.ToString(Number, 2)); //OUTPUT : 1111 To convert decimal number to octal format use base 8 int Number = 15; Console.WriteLine(Convert.ToString(Number, 8)); //OUTPUT : 17 To conv...

The URL for the credits label. Defaults to: http://www.highcharts.com. credits: { text: 'StackOverflow.com', href: 'http://stackoverflow.com' },

The apply and call methods in every function allow it to provide a custom value for this. function print() { console.log(this.toPrint); } print.apply({ toPrint: "Foo" }); // >> "Foo" print.call({ toPrint: "Foo" }); // >> "Foo" You mig...

Normally your tests should be created in such a way that execution order is no concern. However there is always going to be an edge case were you need to break that rule. The one scenario I came across was with R.NET whereby in a given process you can only initialize one R Engine and once disposed ...

let sel = document.getSelection(); let text = sel.toString(); console.log(text); // logs what the user selected Alternatively, since the toString member function is called automatically by some functions when converting the object to a string, you don't always have to call it yourself. console...

package { import flash.events.TimerEvent; import flash.utils.Timer; public class CountdownTimer extends Timer { public var time:Number = 0; public function CountdownTimer(time:Number = Number.NEGATIVE_INFINITY, delay:Number = 1000) { super(delay, repeatCount); ...

// RawRepresentable has an associatedType RawValue. // For this struct, we will make the compiler infer the type // by implementing the rawValue variable with a type of String // // Compiler infers RawValue = String without needing typealias // struct NotificationName: RawRepresentable { ...

We define the type of boolean expressions whose atoms are identified by strings as type expr = | Atom of string | Not of expr | And of expr * expr | Or of expr * expr and can evaluate these expressions using an oracle : string -> bool giving the values of the atoms we find as follows: le...

Holy Grail layout is a layout with a fixed height header and footer, and a center with 3 columns. The 3 columns include a fixed width sidenav, a fluid center, and a column for other content like ads (the fluid center appears first in the markup). CSS Flexbox can be used to achieve this with a very s...

A simple example on how to read a UTF text file synchronously. import flash.filesystem.File; import flash.filesystem.FileMode; import flash.filesystem.FileStream; //First, get a reference to the file you want to load var myFile:File = File.documentsDirectory.resolvePath("lifestory.txt&...

This is MATLAB's long-winded way of saying that it cannot find the function that you're trying to call. There are a number of reasons you could get this error: That function was introduced after your current version of MATLAB The MATLAB online documentation provides a very nice feature which allow...

It is considered good practice to use a prefix when creating git archives, so that extraction will place all files inside a directory. To create an archive of HEAD with a directory prefix: git archive --output=archive-HEAD.zip --prefix=src-directory-name HEAD When extracted all the files will be...

var express = require('express'); var cors = require('cors'); // Use cors module for enable Cross-origin resource sharing var app = express(); app.use(cors()); // for all routes var port = process.env.PORT || 8080; app.get('/', function(req, res) { var info = { 'string_value...

Node.js has 3 basic ways to handle exceptions/errors: try-catch block error as the first argument to a callback emit an error event using eventEmitter try-catch is used to catch the exceptions thrown from the synchronous code execution. If the caller (or the caller's caller, ...) used try/ca...

In Terminal on your Mac operating system, enter the following 2 commands: lsbom -f -l -s -pf /var/db/receipts/org.nodejs.pkg.bom | while read f; do sudo rm /usr/local/${f}; done sudo rm -rf /usr/local/lib/node /usr/local/lib/node_modules /var/db/receipts/org.nodejs.*