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The following example uses expect and receive to mock an Order's call to a CreditCardService, so that the test passes only if the call is made without having to actually make it. class Order def cancel CreditCardService.instance.refund transaction_id end end describe Order do des...

Clear the canvas using compositing operation. This will clear the canvas independent of transforms but is not as fast as clearRect(). ctx.globalCompositeOperation = 'copy'; anything drawn next will clear previous content.

Most Common Lisp implementations will try to load an init file on startup: ImplementationInit fileSite/System Init fileABCL$HOME/.abclrcAllegro CL$HOME/.clinit.clECL$HOME/.eclrcClasp$HOME/.clasprcCLISP$HOME/.clisprc.lispClozure CLhome:ccl-init.lisp or home:ccl-init.fasl or home:.ccl-init.lispCMUCL$...

Some programmers think that it is a good idea to save space by using a null to represent an empty array or collection. While it is true that you can save a small amount of space, the flipside is that it makes your code more complicated, and more fragile. Compare these two versions of a method for ...

Common Lisp has a way to influence the compilation strategies. It makes sense to define your preferred values. Optimization values are between 0 (unimportant) and 3 (extremely important). 1 is the neutral value. It's useful to always use safe code (safety = 3) with all runtime checks enabled. Not...

In features/step_definitions/documentation.rb: When /^I go to the "([^"]+)" documentation$/ do |section| path_part = case section when "Documentation" "documentation" else raise "Unknown documentation section: #{section...

Detailed instructions on getting filemaker set up or installed.

zsh loads configuration from the ~/.zshrc file on startup. If you make changes to that file, you can either restart zsh or run the following command to reload the configuration. . ~/.zshrc You can alias this useful command in your ~/.zshrc like this: alias reload=". ~/.zshrc"

Detailed instructions on getting yarn set up or installed. If you have npm installed on your system: npm install --global yarn On macOS: via Homebrew: brew install yarn via MacPorts: sudo port install yarn (node will be installed if not present) On Windows: via Chocolatey: choco install...

Some Java programmers have a general aversion to throwing or propagating exceptions. This leads to code like the following: public Reader getReader(String pathname) { try { return new BufferedReader(FileReader(pathname)); } catch (IOException ex) { System.out.println(&q...

mod_rewrite must be enabled before being used on an Apache server. Debian/Ubuntu Run a2enmod rewrite Then restart Apache with service apache2 restart General case Add or uncomment the following line in the static configuration file (such as httpd.conf): LoadModule rewrite_module modules/mod_re...

There are many time zones around the world, it is important to make sure your server is set to the right one. This is done in .htaccess by using: SetEnv TZ America/Indianapolis A few example of possible other time zones: America/Los_Angeles America/Los_Angeles - Pacific Time Pacific/Honolulu...

ExecutorService ExecutorService executor = Executors.newFixedThreadPool(50); It is simple and easy to use. It hides low level details of ThreadPoolExecutor. I prefer this one when number of Callable/Runnable tasks are small in number and piling of tasks in unbounded queue does not increase m...

Let's have a look at various options to wait for completion of tasks submitted to Executor ExecutorService invokeAll() Executes the given tasks, returning a list of Futures holding their status and results when everything is completed. Example: import java.util.concurrent.*; import ja...

We can also specify that a virtual function is pure virtual (abstract), by appending = 0 to the declaration. Classes with one or more pure virtual functions are considered to be abstract, and cannot be instantiated; only derived classes which define, or inherit definitions for, all pure virtual fun...

Consider these two micro-benchmarks: The first benchmark simply creates, starts and joins threads. The thread's Runnable does no work. public class ThreadTest { public static void main(String[] args) throws Exception { while (true) { long start = System.nanoTime(); ...

Starting with a binary image, bwImg, which contains a number of connected objects. >> bwImg = imread('blobs.png'); >> figure, imshow(bwImg), title('Binary Image') To measure properties (e.g., area, centroid, etc) of every object in the image, use regionprops: >> stats = reg...

Conditions can also be expressions: $myInput = 0 switch($myInput) { # because the result of the expression, 4, # does not equal our input this block should not be run. (2+2) { 'True. 2 +2 = 4' } # because the result of the expression, 0, # does equal our input this ...

The simple and most obvious way to use recursion to get the Nth term of the Fibonnaci sequence is this int get_term_fib(int n) { if (n == 0) return 0; if (n == 1) return 1; return get_term_fib(n - 1) + get_term_fib(n - 2); } However, this algorithm does not scale for higher ...

Detailed instructions on getting tizen set up or installed. You can start developing Tizen apps on commercialized devices : https://wiki.tizen.org/wiki/Devices Or https://wiki.tizen.org/wiki/ReferenceDevices Last option is to install Tizen from scratch on existing Hardware (x86, ARM etc) : htt...