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Function EnableShift() 'This function enables the SHIFT key at startup. This action causes 'the Autoexec macro and the Startup properties to be bypassed 'if the user holds down the SHIFT key when the user opens the database. On Error GoTo errEnableShift Dim db As DAO.Database Dim p...

Tuples can be compared based on their elements. As an example, an enumerable whose elements are of type Tuple can be sorted based on comparisons operators defined on a specified element: List<Tuple<int, string>> list = new List<Tuple<int, string>>(); list.Add(new Tuple<...

References behaves similarly, but not entirely like const pointers. A reference is defined by suffixing an ampersand & to a type name. int i = 10; int &refi = i; Here, refi is a reference bound to i. References abstracts the semantics of pointers, acting like an alias to the underlying...

The strchr and strrchr functions find a character in a string, that is in a NUL-terminated character array. strchr return a pointer to the first occurrence and strrchr to the last one. #include <stdio.h> #include <stdlib.h> #include <string.h> int main(void) { char toSe...

To use the IronPython command line, open ipy.exe or ipy64.exe. Both files are located in the path that was selected during installation. By default they will be located at C:\Program Files\IronPython 2.7\. Then start writing your statements directly in the IronPython command line. For example: pr...

In its most basic form, an object that implements IEnumerable represents a series of objects. The objects in question can be iterated using the c# foreach keyword. In the example below, the object sequenceOfNumbers implements IEnumerable. It represents a series of integers. The foreach loop iterate...

ALTER TABLE EMPLOYEES ADD pk_EmployeeID PRIMARY KEY (ID) This will add a Primary key to the table Employees on the field ID. Including more than one column name in the parentheses along with ID will create a Composite Primary Key. When adding more than one column, the column names must be separat...

The default position of an element is static. To quote MDN: This keyword lets the element use the normal behavior, that is it is laid out in its current position in the flow. The top, right, bottom, left and z-index properties do not apply. .element{ position:static; }

You can define implementation for specific instantiations of a template class/method. For example if you have: template <typename T> T sqrt(T t) { /* Some generic implementation */ } You can then write: template<> int sqrt<int>(int i) { /* Highly optimized integer implement...

Class methods present alternate ways to build instances of classes. To illustrate, let's look at an example. Let's suppose we have a relatively simple Person class: class Person(object): def __init__(self, first_name, last_name, age): self.first_name = first_name self.last...

raw_data = {'first_name': ['John', 'Jane', 'Jim'], 'last_name': ['Doe', 'Smith', 'Jones'], 'department': ['Accounting', 'Sales', 'Engineering'],} df = pd.DataFrame(raw_data,columns=raw_data.keys()) df.to_csv('data_file.csv')

This is a very common Exception. It causes your application to stop during the start or execution of your app. In the LogCat you see the message: android.content.ActivityNotFoundException : Unable to find explicit activity class; have you declared this activity in your AndroidManifest.xml? In ...

The cx and cy values designate the location of the center of the circle. The r attribute specifies the size of the radius of the circle. <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> <circle cx="40" cy="40&q...

class Car { public position: number = 0; private speed: number = 42; move() { this.position += this.speed; } } In this example, we declare a simple class Car. The class has three members: a private property speed, a public property position and a public met...

class Car { public position: number = 0; protected speed: number = 42; move() { this.position += this.speed; } } class SelfDrivingCar extends Car { move() { // start moving around :-) super.move(); super.move(); } } ...

public class Singleton { private static final Singleton INSTANCE = new Singleton(); private Singleton() {} public static Singleton getInstance() { return INSTANCE; } } It can be argued that this example is effectively lazy initialization. Section 12.4.1 of ...

To increment date objects in Javascript, we can usually do this: var checkoutDate = new Date(); // Thu Jul 21 2016 10:05:13 GMT-0400 (EDT) checkoutDate.setDate( checkoutDate.getDate() + 1 ); console.log(checkoutDate); // Fri Jul 22 2016 10:05:13 GMT-0400 (EDT) It is possible to use setD...

countMatches method from org.apache.commons.lang3.StringUtils is typically used to count occurences of a substring or character in a String: import org.apache.commons.lang3.StringUtils; String text = "One fish, two fish, red fish, blue fish"; // count occurrences of a substring Str...

Start with an iterable which needs to be grouped lst = [("a", 5, 6), ("b", 2, 4), ("a", 2, 5), ("c", 2, 6)] Generate the grouped generator, grouping by the second element in each tuple: def testGroupBy(lst): groups = itertools.groupby(lst, key=lambda...

Scalars are Perl's most basic data type. They're marked with the sigil $ and hold a single value of one of three types: a number (3, 42, 3.141, etc.) a string ('hi', "abc", etc.) a reference to a variable (see other examples). my $integer = 3; # number my $str...