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The difference between Classes, Objects, and Instances
...ject's code. An object is an instance of a class
for example if you say
String word = new String();
the class is the String class, which describes the object (instance) word.
When a class is declared, no memory is allocated so class is just a template.
When the object of the class is declared...
How to play a local video with Swift?
...e provided solution did not work for me.
private func playVideo(from file:String) {
let file = file.components(separatedBy: ".")
guard let path = Bundle.main.path(forResource: file[0], ofType:file[1]) else {
debugPrint( "\(file.joined(separator: ".")) not found")
return
...
How do I concatenate or merge arrays in Swift?
...
If you're merging more than 2 arrays (or strings or whatever else), restrain yorself from using the + operator, it generates absolutely insane compile times.
– lawicko
Oct 21 '19 at 8:10
...
Is Redis just a cache?
...e, Redis lets you operate on the values. There are 5 data types in Redis - Strings, Sets, Hash, Lists and Sorted Sets. Each data type exposes various operations.
The best way to understand Redis is to model an application without thinking about how you are going to store it in a database.
Lets sa...
Does using “new” on a struct allocate it on the heap or stack?
...tructor (e.g. new Guid()) or a parameterful constructor (e.g. new Guid(someString)). These generate significantly different IL. To understand why, you need to compare the C# and CLI specs: according to C#, all value types have a parameterless constructor. According to the CLI spec, no value types ha...
Should I pass a shared_ptr by reference? [duplicate]
...n some implementations of std::SP). It's the same if I was passing an std::string object (either const std::string& or by value).
– wolfgang
Dec 5 '11 at 13:36
...
Copying a HashMap in Java
...til.HashMap;
public class CloneHashMap {
public static void main(String a[]) {
HashMap hashMap = new HashMap();
HashMap hashMap1 = new HashMap();
hashMap.put(1, "One");
hashMap.put(2, "Two");
hashMap.put(3, "Three");
System.out.pr...
jQuery / Javascript - How do I convert a pixel value (20px) to a number value (20)
I know jQuery has a helper method for parsing unit strings into numbers. What is the jQuery method to do this?
6 Answers
...
How is the AND/OR operator represented as in Regular Expressions?
..., "part2" (answer 2) or "part1, part2" (answer 3).
I now try to match the string given by the user with the following, automatically created, regex expression:
...
Assigning default value while creating migration file
...generator command either but was able to specify a default value for a new string column as follows by amending the generated migration file before applying "rake db:migrate":
class AddColumnToWidgets < ActiveRecord::Migration
def change
add_column :widgets, :colour, :string, default: 'red...