Tutorial by Topics: ons

Python makes regular expressions available through the re module. Regular expressions are combinations of characters that are interpreted as rules for matching substrings. For instance, the expression 'amount\D+\d+' will match any string composed by the word amount plus an integral number, separate...

for {clauses} body for {clauses} yield body for (clauses) body for (clauses) yield body ParameterDetailsforRequired keyword to use a for loop/comprehensionclausesThe iteration and filters over which the for works.yieldUse this if you want to create or 'yield' a collection. Using yield wil...

While not required, constructors in Java are methods recognized by the compiler to instantiate specific values for the class which may be essential to the role of the object. This topic demonstrates proper usage of Java class constructors. The Java Language Specification talks at length about ...

Notification.requestPermission(callback) Notification.requestPermission().then(callback, rejectFunc) new Notification(title, options) notification.close() The Notifications API was designed to allow browser access to notifying the client. Support by browsers might be limited. Also suppo...

[[ -OP $filename ]] [[ $file1 -OP $file2 ]] [[ -z $string ]] [[ -n $string ]] [[ "$string1" == "$string2" ]] [[ "$string1" == $pattern ]] The [[ … ]] syntax surrounds bash built-in conditional expressions. Note that spaces are required on either side of th...

WITH QueryName [(ColumnName, ...)] AS (   SELECT ... ) SELECT ... FROM QueryName ...; WITH RECURSIVE QueryName [(ColumnName, ...)] AS (   SELECT ...   UNION [ALL]   SELECT ... FROM QueryName ... ) SELECT ... FROM QueryName ...; Official documentation: WITH clause A Common ...

transition: [transition-property] [transition-duration] [transition-timing-function] [transition-delay]; ParameterDetailstransition-propertyThe specific CSS property whose value change needs to be transitioned (or) all, if all the transitionable properties need to be transitioned.transition-...

There currently aren't any installation packages provided for Bosun or Scollector, only binaries on the Bosun release page. It is up to the end user to find the best way to deploy the files and run them as a service.

preg_replace($pattern, $replacement, $subject, $limit = -1, $count = 0); preg_replace_callback($pattern, $callback, $subject, $limit = -1, $count = 0); preg_match($pattern, $subject, &$matches, $flags = 0, $offset = 0); preg_match_all($pattern, $subject, &$matches, $flags = PREG_PATTERN...

async and await build on top of promises and generators to express asynchronous actions inline. This makes asynchronous or callback code much easier to maintain. Functions with the async keyword return a Promise, and can be called with that syntax. Inside an async function the await keyword can be...

An exception is an object that represents the occurrence of an exceptional condition. In other words, it indicates that something went wrong. In Ruby, exceptions are often referred to as errors. That's because the base Exception class exists as a top-level exception object element, but user-defin...

Function([DISTINCT] expression) -DISTINCT is an optional parameter AVG ( [ ALL | DISTINCT ] expression ) COUNT( { [ALL | DISTINCT ] expression ] | * } ) GROUPING(<column_expression>) MAX ( [ ALL | DISTINCT ] expression ) MIN ( [ ALL | DISTINCT ] expression ) SUM ( [ ALL | DISTINCT ] e...

JSON - Java Script Object Notation , Postgresql support JSON Data type since 9.2 version. There are some predefined function and operators to access the JSON data. The -> operator returns the key of JSON column. The ->> operator returns the value of JSON Column.

Go supports constants of character, string, boolean, and numeric values.

ActionScript 3 is the programming language for the Adobe Flash Player and Adobe AIR runtime environments. It is object-oriented ECMAScript based language used primary for native application development on desktop (Windows/Mac) and mobile (iOS/Android) devices. Adobe learning resources: http://ww...