Tutorial by Examples: g

The GNU gprof profiler, gprof, allows you to profile your code. To use it, you need to perform the following steps: Build the application with settings for generating profiling information Generate profiling information by running the built application View the generated profiling inf...

std::ostringstream is a class whose objects look like an output stream (that is, you can write to them via operator<<), but actually store the writing results, and provide them in the form of a stream. Consider the following short code: #include <sstream> #include <string> ...

The QueryClose event is raised whenever a form is about to be closed, whether it's via user action or programmatically. The CloseMode parameter contains a VbQueryClose enum value that indicates how the form was closed: ConstantDescriptionValuevbFormControlMenuForm is closing in response to user act...

import groovy.json.JsonSlurper; def jsonSlurper = new JsonSlurper() def obj = jsonSlurper.parseText('{ "foo": "bar", "baz": [1] }') assert obj.foo == 'bar' assert obj.baz == [1]

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' In addition to maps, lists and primitives groovy.json.JsonOutput also supports a POJOs serialitzation: import groovy.json.JsonOutput; ...

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' def pretty = JsonOutput.prettyPrint(json) assert pretty == '''{ "foo": "bar", "baz": [ ...

Loading the Incubator into your project Add the following lines of code to your loader file $loader = new Phalcon\Loader(); $loader->registerNamespaces([ 'Phalcon' => '/path/to/your/vendor/phalcon/incubator/Library/Phalcon/', // any other namespaces you have loaded // ... ...

Use list() to quick assign a list of variable values into an array. See also compact() // Assigns to $a, $b and $c the values of their respective array elements in $array with keys numbered from zero list($a, $b, $c) = $array; With PHP 7.1 (currently in beta) you will be able to use s...

To create a custom standalone Gradle plug-in using java (you can also use Groovy) you have to create a structure like this: plugin |-- build.gradle |-- settings.gradle |-- src |-- main | |-- java | |-- resources | |-- META-INF | |-- gradle-plugins ...

Foreign keys enables you to define relationship between two tables. One (parent) table need to have primary key that uniquely identifies rows in the table. Other (child) table can have value of the primary key from the parent in one of the columns. FOREIGN KEY REFERENCES constraint ensures that valu...

Let's assume that we have one row in Company table with companyId 1. We can insert row in employee table that has companyId 1: insert into Employee values (17, 'John', 1) However, we cannot insert employee that has non-existing CompanyId: insert into Employee values (17, 'John', 111111) Msg ...

FOREIGN KEY constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table CompanyId column but don't have foreign key relationship. ALTER TABLE statement enables you to add foreign key constraint on an existing c...

FOREIGN KEY columns with constraint can be added on existing tables that are still not in relationship. Imagine that we have Company and Employee tables where Employee table don't have CompanyId column. ALTER TABLE statement enables you to add new column with foreign key constraint that references ...

sys.foreignkeys system view returns information about all foreign key relationships in database: select name, OBJECT_NAME(referenced_object_id) as [parent table], OBJECT_NAME(parent_object_id) as [child table], delete_referential_action_desc, update_referential_action_desc from sys.foreign...

Create a set local set = {} -- empty set Create a set with elements by setting their value to true: local set = {pear=true, plum=true} -- or initialize by adding the value of a variable: local fruit = 'orange' local other_set = {[fruit] = true} -- adds 'orange' Add a member to the ...

Swift let bundleIdentifier = NSBundle.mainBundle().bundleIdentifier() NSUserDefaults.standardUserDefaults().removePersistentDomainForName(bundleIdentifier) Objective-C NSString *bundleIdentifier = [[NSBundle mainBundle] bundleIdentifier]; [[NSUserDefaults standardUserDefaults] removePersi...

After installing a Java SDK, it is advisable to check that it is ready to use. You can do this by running these two commands, using your normal user account: $ java -version $ javac -version These commands print out the version information for the JRE and JDK (respectively) that are on your sh...

>>> import os >>> os.stat(path_to_file).st_size == 0 or >>> import os >>> os.path.getsize(path_to_file) > 0 However, both will throw an exception if the file does not exist. To avoid having to catch such an error, do this: import os def is_empty_...

A commonly used utility library is Lodash. To install it into your Aurelia CLI driven application first you need to install it using Npm. npm install lodash --save Now in your preferred IDE/code editor open up the following file in your project directory: aurelia_project/aurelia.json and scroll do...

Boost program options provides a simple and safe way to parse and handle command line arguments. #include <boost/program_options.hpp> #include <string> #include <iostream> int main(int argc, char** argv) { namespace po = boost::program_options; po::variables_map vm; ...