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To remove a value from a set, use .delete() method: mySet.delete(some_val); This function will return true if the value existed in the set and was removed, or false otherwise.

To check if a given value exists in a set, use .has() method: mySet.has(someVal); Will return true if someVal appears in the set, false otherwise.

One is able to nest one exception / try catch block inside the other. This way one can manage small blocks of code which are capable of working without disrupting your whole mechanism. try { //some code here try { //some thing which throws an exception. For Eg : divide by 0 ...

Hibernate has some strategies of inheritance. The JOINED inheritance type do a JOIN between the child entity and parent entity. The problem with this approach is that Hibernate always bring the data of all involved tables in the inheritance. Per example, if you have the entities Bicycle and Mounta...

A hash is a function that converts a variable length sequence of bytes to a fixed length sequence. Hashing files can be advantageous for many reasons. Hashes can be used to check if two files are identical or verify that the contents of a file haven't been corrupted or changed. You can use hashlib ...

The map operation is a useful tool when working with arrays and vectors, but it can also be used to deal with Option values in a functional way. fn main() { // We start with an Option value (Option<i32> in this case). let some_number = Some(9); // Let's do some consecutive ...

public class MainApplication extends Application { private static Context context; //application context private Handler mainThreadHandler; private Toast toast; public Handler getMainThreadHandler() { if (mainThreadHandler == null) { mainThreadHand...

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Manual Global Installation For OS X and Linux: Bring up Terminal, Bash, or your normal shell. Type the following into Terminal/Bash: # Download latest stable release using the code below or browse to github.com/drush-ops/drush/releases. php -r "readfile('http://files.drush.org/drus...

Manual installation Type below commands in Terminal. php -r "readfile('http://files.drush.org/drush.phar');" > drush chmod +x drush sudo mv drush /usr/local/bin drush init # Add alias in bash startup file. Composer Assuming composer is installed. composer global require drush/...

Onsen UI is an open-source framework that helps you build hybrid apps with native like performance. It can be used along with several well known JavaScript frameworks such as AngularJS (1 & 2), ReactJS and jQuery. Loading OnsenUI in a project is as easy as writing some standard tags of HTML in ...

One common use for the FOR XML function is to concatenate the values of multiple rows. Here's an example using the Customers table: SELECT STUFF( (SELECT ';' + Email FROM Customers where (Email is not null and Email <> '') ORDER BY Email ASC FOR XM...

;; disable automatic loading of packages after the init file (setq package-enable-at-startup nil) ;; instead load them explicitly (package-initialize) ;; refresh package descriptions (unless package-archive-contents (package-refresh-contents)) ;;; use-package initialization ;;; install ...

app.UseMvc(routes => { routes.MapRoute( name: "default", template: "{controller=Home}/{action=Index}/{id?}"); }); This will match requests for /Home/Index, /Home/Index/123 and /

iota can be used in expressions, so it can also be used to assign values other than simple incrementing integers starting from zero. To create constants for SI units, use this example from Effective Go: type ByteSize float64 const ( _ = iota // ignore first value by assigning to b...

The value of iota is still incremented for every entry in a constant list even if iota is not used: const ( // iota is reset to 0 a = 1 << iota // a == 1 b = 1 << iota // b == 2 c = 3 // c == 3 (iota is not used but still incremented) d = 1 << iota ...

Because iota is incremented after each ConstSpec, values within the same expression list will have the same value for iota: const ( bit0, mask0 = 1 << iota, 1<<iota - 1 // bit0 == 1, mask0 == 0 bit1, mask1 // bit1 == 2, mask1 == 1 _, _ ...

Iota can be very useful when creating a bitmask. For instance, to represent the state of a network connection which may be secure, authenticated, and/or ready, we might create a bitmask like the following: const ( Secure = 1 << iota // 0b001 Authn // 0b010 Ready ...

Often times, responsive web design involves media queries, which are CSS blocks that are only executed if a condition is satisfied. This is useful for responsive web design because you can use media queries to specify different CSS styles for the mobile version of your website versus the desktop ver...

Joining on a subquery is often used when you want to get aggregate data (such as Count, Avg, Max, or Min) from a child/details table and display that along with records from the parent/header table. For example, you may want to retrieve the top/first child row based on Date or Id or maybe you want a...