Tutorial by Examples: ga

Functions are first-class citizens in Kotlin. You can obtain a reference on it using double colons and then pass it to another function: fun isPositive(x: Int) = x > 0 val numbers = listOf(-2, -1, 0, 1, 2) println(numbers.filter(::isPositive)) // [1, 2]

When the GNU project needed an assembler for the x86 family, they went with the AT&T version (and its syntax) that was associated with Unix rather than the Intel/Microsoft version.

int a; std::cout << a; // Undefined behavior! This results in undefined behavior, because a is uninitialised. It is often, incorrectly, claimed that this is because the value is "indeterminate", or "whatever value was in that memory location before". However, it is th...

In order to record audio from a user's microphone, we must first gain permission from the user to access the device: navigator.mediaDevices.getUserMedia({ audio: true }) .then(successCallback) .catch(failureCallback); On success, our successCallback will be called with a MediaStream ob...

Download and extract the OSGi starter kit for your platform from Equinox download page for Neon release. Start the framework from the rt/plugins folder with the following command (or your platform's rt executable from the rt folder): rt/plugins$ java -jar org.eclipse.equinox.launcher_1.3.200.v2016...

One of the most elementary DCG nonterminals is ... //0, which can be read as "anything at all": ... --> [] | [_], ... . It can be used to describe a list Ls that contains the element E via: phrase(( ..., [E], ... ), Ls)

To load a bundled image: package com.example; public class ExampleApplication { private Image getIcon() throws IOException { URL imageURL = ExampleApplication.class.getResource("icon.png"); return ImageIO.read(imageURL); } }

You can use the Substring method to get any number of characters from a string at any given location. However, if you only want a single character, you can use the string indexer to get a single character at any given index like you do with an array: string s = "hello"; char c = s[1]; //...

5.2 Objects in lua are garbage collected. Sometimes, you need to free some resource, want to print a message or do something else when an object is destroyed (collected). For this, you can use the __gc metamethod, which gets called with the object as argument when the object is destroyed. You could...

[^0-9a-zA-Z] This will match all characters that are neither numbers nor letters (alphanumerical characters). If the underscore character _ is also to be negated, the expression can be shortened to: [^\w] Or: \W In the following sentences: Hi, what's up? I can't wait for 2017!...

[^0-9] This will match all characters that are not ASCII digits. If Unicode digits are also to be negated, the following expression can be used, depending on your flavor/language settings: [^\d] This can be shortened to: \D You may need to enable Unicode character properties support expl...

pip doesn't current contain a flag to allow a user to update all outdated packages in one shot. However, this can be accomplished by piping commands together in a Linux environment: pip list --outdated --local | grep -v '^\-e' | cut -d = -f 1 | xargs -n1 pip install -U This command takes all pa...

pip doesn't current contain a flag to allow a user to update all outdated packages in one shot. However, this can be accomplished by piping commands together in a Windows environment: for /F "delims= " %i in ('pip list --outdated --local') do pip install -U %i This command takes all pa...

really_neat.info name = Really Neat Module description = Provides a really neat page for your site core = 7.x really_neat.module <?php /** * @file * Hook implementation and shared functions for the Really Neat Module. */ /** * Implements hook_menu(). */ function really_nea...

The idea here is to move the computationally intensive jobs to C (using special macros), independent of Python, and have the C code release the GIL while it's working. #include "Python.h" ... PyObject *pyfunc(PyObject *self, PyObject *args) { ... Py_BEGIN_ALLOW_THREADS //...

Because LINQ uses deferred execution, we can have a query object that doesn't actually contain the values, but will return the values when evaluated. We can thus dynamically build the query based on our control flow, and evaluate it once we are finished: IEnumerable<VehicleModel> BuildQuery(i...

Sometimes you need to keep a linear (non-branching) history of your code commits. If you are working on a branch for a while, this can be tricky if you have to do a regular git pull since that will record a merge with upstream. [alias] up = pull --rebase This will update with your upstream so...

/// <summary> /// Registers a background task in the system waiting to trigger /// </summary> /// <param name="taskName">Name of the task. Has to be unique</param> /// <param name="taskEntryPoint">Entry point (Namespace) of the class (has to impl...

var trigger = new ApplicationTrigger(); TaskHandlerMentionedInThisTutorial.RegisterTask(TaskName, entryPoint, trigger, null, true); await trigger.RequestAsync();

/// <summary> /// Unregister a single background task with given name /// </summary> /// <param name="taskName">task name</param> /// <param name="cancelTask">true if task should be cancelled, false if allowed to finish</param> public void...