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Inheritance in Python is based on similar ideas used in other object oriented languages like Java, C++ etc. A new class can be derived from an existing class as follows. class BaseClass(object): pass class DerivedClass(BaseClass): pass The BaseClass is the already existing (parent)...

Instance variables are unique for each instance, while class variables are shared by all instances. class C: x = 2 # class variable def __init__(self, y): self.y = y # instance variable C.x # 2 C.y # AttributeError: type object 'C' has no attribute 'y' c1 = C(3) c1....

The idea of bound and unbound methods was removed in Python 3. In Python 3 when you declare a method within a class, you are using a def keyword, thus creating a function object. This is a regular function, and the surrounding class works as its namespace. In the following example we declare method ...

Python 2.x2.2.0 New-style classes were introduced in Python 2.2 to unify classes and types. They inherit from the top-level object type. A new-style class is a user-defined type, and is very similar to built-in types. # new-style class class New(object): pass # new-style instance new = N...

if [[ $1 -eq 1 ]]; then echo "1 was passed in the first parameter" elif [[ $1 -gt 2 ]]; then echo "2 was not passed in the first parameter" else echo "The first parameter was not 1 and is not more than 2." fi The closing fi is necessary, but the eli...

#! /bin/bash for i in {1..10}; do # {1..10} expands to "1 2 3 4 5 6 7 8 9 10" echo $i done This outputs the following: 1 2 3 4 5 6 7 8 8 10

In the same module Inside a module named "MyModule", Xcode generates a header named MyModule-Swift.h which exposes public Swift classes to Objective-C. Import this header in order to use the Swift classes: // MySwiftClass.swift in MyApp import Foundation // The class must be `public`...

If MyFramework contains Objective-C classes in its public headers (and the umbrella header), then import MyFramework is all that's necessary to use them from Swift. Bridging headers A bridging header makes additional Objective-C and C declarations visible to Swift code. When adding project files, ...

Supplying pow() with 3 arguments pow(a, b, c) evaluates the modular exponentiation ab mod c: pow(3, 4, 17) # 13 # equivalent unoptimized expression: 3 ** 4 % 17 # 13 # steps: 3 ** 4 # 81 81 % 17 # 13 For built-in types using modular exponentiation is only possible...

// use Write trait that contains write() function use std::io::Write; fn main() { std::io::stdout().write(b"Hello, world!\n").unwrap(); } The std::io::Write trait is designed for objects which accept byte streams. In this case, a handle to standard output is acquired with ...

Concatenate strings with the + operator to produce a new string: let name = "John" let surname = "Appleseed" let fullName = name + " " + surname // fullName is "John Appleseed" Append to a mutable string using the += compound assignment operator, or usi...

The -import-objc-header flag specifies a header for swiftc to import: // defs.h struct Color { int red, green, blue; }; #define MAX_VALUE 255 // demo.swift extension Color: CustomStringConvertible { // extension on a C struct public var description: String { return &q...

A module map can simply import mymodule by configuring it to read C header files and make them appear as Swift functions. Place a file named module.modulemap inside a directory named mymodule: Inside the module map file: // mymodule/module.modulemap module mymodule { header "defs.h&q...

public class TrustLoader { public static void main(String args[]) { try { //Gets the inputstream of a a trust store file under ssl/rpgrenadesClient.jks //This path refers to the ssl folder in the jar file, in a jar file in the same directory ...

A rebase switches the meaning of "ours" and "theirs": git checkout topic git rebase master # rebase topic branch on top of master branch Whatever HEAD's pointing to is "ours" The first thing a rebase does is resetting the HEAD to master; before cherry-picking...

You have up to 5 sources for git configuration: 6 files: %ALLUSERSPROFILE%\Git\Config (Windows only) (system) <git>/etc/gitconfig, with <git> being the git installation path. (on Windows, it is <git>\mingw64\etc\gitconfig) (system) $XDG_CONFIG_HOME/git/config (Linux/Mac on...

Using the strtotime() function combined with date() you can parse different English text descriptions to dates: // Gets the current date echo date("m/d/Y", strtotime("now")), "\n"; // prints the current date echo date("m/d/Y", strtotime("10 September 2...

Check whether a string is empty: if str.isEmpty { // do something if the string is empty } // If the string is empty, replace it with a fallback: let result = str.isEmpty ? "fallback string" : str Check whether two strings are equal (in the sense of Unicode canonical equivale...

A Swift String is made of Unicode code points. It can be decomposed and encoded in several different ways. let str = "ที่👌①!" Decomposing Strings A string's characters are Unicode extended grapheme clusters: Array(str.characters) // ["ที่", "👌", "①", ...

Per paragraph 6.5/5 of both C99 and C11, evaluation of an expression produces undefined behavior if the result is not a representable value of the expression's type. For arithmetic types, that's called an overflow. Unsigned integer arithmetic does not overflow because paragraph 6.2.5/9 applies, ca...