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To match something that does not contain a given string, one can use negative lookahead: Regex syntax: (?!string-to-not-match) Example: //not matching "popcorn" String regexString = "^(?!popcorn).*$"; System.out.println("[popcorn] " + ("popcorn".matches(r...

lib.rs: pub fn to_test(output: bool) -> bool { output } Each file in the tests/ folder is compiled as single crate. tests/integration_test.rs extern crate test_lib; use test_lib::to_test; #[test] fn test_to_test(){ assert_eq!(to_test(true), true); }

When you do a groupby you can select either a single column or a list of columns: In [11]: df = pd.DataFrame([[1, 1, 2], [1, 2, 3], [2, 3, 4]], columns=["A", "B", "C"]) In [12]: df Out[12]: A B C 0 1 1 2 1 1 2 3 2 2 3 4 In [13]: g = df.groupby(...

It is possible to define custom string interpolators in addition to the built-in ones. my"foo${bar}baz" Is expanded by the compiler to: new scala.StringContext("foo", "baz").my(bar) scala.StringContext has no my method, therefore it can be provided by implicit c...

Example Using Activity w/ LocationRequest /* * This example is useful if you only want to receive updates in this * activity only, and have no use for location anywhere else. */ public class LocationActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, ...

If you want to parse a String to enum with Gson: {"status" : "open"} public enum Status { @SerializedName("open") OPEN, @SerializedName("waiting") WAITING, @SerializedName("confirm") CONFIRM, @SerializedName(&...

SELECT s.name + '.' + t.NAME AS TableName, SUM(a.used_pages)*8 AS 'TableSizeKB' --a page in SQL Server is 8kb FROM sys.tables t JOIN sys.schemas s on t.schema_id = s.schema_id LEFT JOIN sys.indexes i ON t.OBJECT_ID = i.object_id LEFT JOIN sys.partitions p ON i.object_id = ...

Since JUnit is a Java library, all you have to do to install it is to add a few JAR files into the classpath of your Java project and you're ready to go. You can download these two JAR files manually: junit.jar & hamcrest-core.jar. If you're using Maven, you can simply add in a dependency into...

Caller info attributes can be used to pass down information about the invoker to the invoked method. The declaration looks like this: using System.Runtime.CompilerServices; public void LogException(Exception ex, [CallerMemberName]string callerMemberName = "", ...

Optional Parameters In TypeScript, every parameter is assumed to be required by the function. You can add a ? at the end of a parameter name to set it as optional. For example, the lastName parameter of this function is optional: function buildName(firstName: string, lastName?: string) { // ...

Returns one of two values depending on the value of a Boolean expression. Syntax: condition ? expression_if_true : expression_if_false; Example: string name = "Frank"; Console.WriteLine(name == "Frank" ? "The name is Frank" : "The name is not Frank"); ...

Boolean(...) will convert any data type into either true or false. Boolean("true") === true Boolean("false") === true Boolean(-1) === true Boolean(1) === true Boolean(0) === false Boolean("") === false Boolean("1") === true Boolean("0") === t...

In themes.xml: <style name="AppTheme" parent="Theme.AppCompat"> <!-- Theme attributes here --> </style> In AndroidManifest.xml: <application android:icon="@mipmap/ic_launcher" android:label="@string/app_name" andr...

You can customize your theme’s color palette. Using framework APIs 5.0 <style name="AppTheme" parent="Theme.Material"> <item name="android:colorPrimary">@color/primary</item> <item name="android:colorPrimaryDark">@color/pri...

In themes.xml: <style name="MyActivityTheme" parent="Theme.AppCompat"> <!-- Theme attributes here --> </style> In AndroidManifest.xml: <application android:icon="@mipmap/ic_launcher" android:label="@string/app_name" ...

Have required JavaScript and CSS files included in your index.html. You can do this by either using the CDN files availiable at the following paths: <link rel="stylesheet" type="text/css" href="//cdn.datatables.net/1.10.12/css/jquery.dataTables.css"> <scr...

XML elements often nest, have data in attributes and/or as character data. The way to capture this data is by using ,attr and ,chardata respectively for those cases. var doc = ` <parent> <child1 attr1="attribute one"/> <child2>and some cdata</child2> </p...

Here is a simple Python command-line program which will connect to a Twitch channel as a bot and respond to a few simple commands. Dependencies: irc Python lib (pip install irc or easy_install irc) Source: https://gist.github.com/jessewebb/65b554b5be784dd7c8d1 import logging import sys f...

Pointer Methods Pointer methods can be called even if the variable is itself not a pointer. According to the Go Spec, . . . a reference to a non-interface method with a pointer receiver using an addressable value will automatically take the address of that value: t.Mp is equivalent to (&t)....

Channels are often used to implement timeouts. func main() { // Create a buffered channel to prevent a goroutine leak. The buffer // ensures that the goroutine below can eventually terminate, even if // the timeout is met. Without the buffer, the send on the channel // blocks fo...