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To check if an element with a specified key exits in a WeakMap, use the .has() method. It returns true if it exits, and otherwise false. const obj1 = {}, obj2 = {}; const weakmap = new WeakMap([[obj1, 7]]); console.log(weakmap.has(obj1)); // true console.log(weakmap.has(obj2)); // false...

You could use "SP_HELPINDEX Table_Name", but Kimberly Tripp has a stored procedure (that can be found here), which is better example, as it shows more about the indexes, including columns and filter definition, for example: Usage: USE Adventureworks EXEC sp_SQLskills_SQL2012_helpindex ...

MailApp is the api from Google App Script that can be used to send mail function sendEmails() { var subject = "A subject for your new app!"; var message = "And this is the very first message" var recipientEmail = "abc@example.com"; MailApp.sendEmail(rec...

Sometimes you need to match a literal (sub-)string with a regular expression despite that substring containing RE metacharacters. While yes, it's possible to write code to insert appropriate backslashes to make that work (using string map) it is easiest to just prefix the pattern with ***=, which ma...

Design (layout XML): <AutoCompleteTextView android:id="@+id/autoCompleteTextView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentTop="true" android:layout_centerHorizontal="true&...

C++11 During exception handling there is a common use case when you catch a generic exception from a low-level function (such as a filesystem error or data transfer error) and throw a more specific high-level exception which indicates that some high-level operation could not be performed (such as b...

A downcast can be used to make use of a subclass's code and data inside of a function taking a parameter of its superclass. class Rat { var color = "white" } class PetRat: Rat { var name = "Spot" } func nameOfRat(🐭: Rat) -> String { guard let petRat = ...

Converts the specified string representation of a date and time to its DateTime equivalent using the specified format and culture-specific format information. The format of the string representation must match the specified format exactly. Convert a specific format string to equivalent DateTime Le...

To check if a value exits in a WeakSet, use the .has() method. const obj1 = {}, obj2 = {}; const weakset = new WeakSet([obj1]); console.log(weakset.has(obj1)); // true console.log(weakset.has(obj2)); // false

import java.util.stream.IntStream; public class Concurrent { public static void printAndWait(String s) { System.out.println(s); try { Thread.sleep(1000); } catch (Exception e) {} } public static void main(String[] args) { Threa...

Description This is a self-contained running example including/showcasing: minimum dependencies needed, Java Configuration, Bean declaration by annotation and Java Configuration, Dependency Injection by Constructor and by Property, and Pre/Post hooks. Dependencies These dependencies are needed in...

The exposition pipe operator, %$%, exposes the column names as R symbols within the left-hand side object to the right-hand side expression. This operator is handy when piping into functions that do not have a data argument (unlike, say, lm) and that don't take a data.frame and column names as arg...

c++17 C++17 introduces int std::uncaught_exceptions() (to replace the limited bool std::uncaught_exception()) to know how many exceptions are currently uncaught. That allows for a class to determine if it is destroyed during a stack unwinding or not. #include <exception> #include <strin...

Controls the instancing characteristics of a class. Attribute VB_Exposed = False Makes the class Private. It cannot be accessed outside of the current project. Attribute VB_Exposed = True Exposes the class Publicly, outside of the project. However, since VB_Createable is ignored in VBA, inst...

Warning! Apply shadows sparingly! Applying shadowing is expensive and is multiplicatively expensive if you apply shadowing inside an animation loop. Instead, cache a shadowed version of your image (or other drawing): At the start of your app, create a shadowed version of your image in a secon...

SCOPE_IDENTITY() returns the last identity value inserted into an identity column in the same scope. A scope is a module: a stored procedure, trigger, function, or batch. Therefore, two statements are in the same scope if they are in the same stored procedure, function, or batch. INSERT INTO ([col...

Example of setting the isolation level: SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED; SELECT * FROM Products WHERE ProductId=1; SET TRANSACTION ISOLATION LEVEL REPEATABLE READ; --return to the default one READ UNCOMMITTED - means that a query in the current transaction can't access the...

Adding dependencies into the build.gradle file. dependencies { .... compile 'com.squareup.retrofit2:retrofit:2.1.0' compile ('com.thoughtworks.xstream:xstream:1.4.7') { exclude group: 'xmlpull', module: 'xmlpull' } .... } Then create Converter Factory public c...

Strikethrough the entire text String sampleText = "This is a test strike"; textView.setPaintFlags(tv.getPaintFlags()| Paint.STRIKE_THRU_TEXT_FLAG); textView.setText(sampleText); Output: This is a test strike Strikethrough only parts of the text String sampleText = "This is a...

To achieve the simplest task in Entity Framework - to connect to an existing database ExampleDatabase on your local instance of MSSQL you have to implement two classes only. First is the entity class, that will be mapped to our database table dbo.People. class Person { public int...