init function for structs

Go doesn’t have implicit constructors. You would likely write something like this. package main import “fmt” type Console struct { X int Y int } func NewConsole() *Console { return &Console{X: 5} } var console Console = *NewConsole() func main() { fmt.Println(console) } Output: {5 0}

Is it OK to put propTypes and defaultProps as static props inside React class?

In fact, it’s exactly the same in terms of performance. React.JS is a relatively new technology, so it’s not clear yet what are considered good practices or don’t. If you want to trust someone, check this AirBNB’s styleguide: import React, { PropTypes } from ‘react’; const propTypes = { id: PropTypes.number.isRequired, url: PropTypes.string.isRequired, text: …

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How do I override inherited methods when using JavaScript ES6/ES2015 subclassing

The solution I found was to create a new function in the subclass that has the same name as the inherited function. In this case push. Then inside the overriding function the inherited function is called via the super keyword. class newArray extends Array{ push(value) { //execute any logic require before pushing value onto array …

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Main method in Scala

To answer your question, have a look on the following : I made a scala class, compiled and decompiled it, and what I got is interesting. class MyScalaClass{ def main(args: Array[String]): Unit = { println(“Hello from main of class”) } } Compiled from “MyScalaClass.scala” public class MyScalaClass { public void main(java.lang.String[]); public MyScalaClass(); } So …

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Scala: Ignore case class field for equals/hascode?

Only parameters in the first parameter section are considered for equality and hashing. scala> case class Foo(a: Int)(b: Int) defined class Foo scala> Foo(0)(0) == Foo(0)(1) res0: Boolean = true scala> Seq(0, 1).map(Foo(0)(_).hashCode) res1: Seq[Int] = List(-1669410282, -1669410282) UPDATE To expose b as a field: scala> case class Foo(a: Int)(val b: Int) defined class Foo …

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Counting instances of a class?

You could consider using a class attribute to provide a counter. Each instance needs only to ask for the next value. They each get something unique. Eg: from itertools import count class Obj(object): _ids = count(0) def __init__(self): = next(self._ids)