Asked  7 Months ago    Answers:  5   Viewed   21 times

If unary +/- operators are used to perform conversions as the Number() casting function, then why do we need unary operators? What's the special need of these unary operators?

 Answers

45

The Unary + operator converts its operand to Number type. The Unary - operator converts its operand to Number type, and then negates it. (per the ECMAScript spec)

In practice, Unary - is used for simply putting negative numbers in normal expressions, e.g.:

var x = y * -2.0;

That's the unary minus operator at work. The Unary + is equivalent to the Number() constructor called as a function, as implied by the spec.

I can only speculate on the history, but the unary +/- operators behave similarly in many C-derived languages. I suspect the Number() behavior is the addition to the language here.

Tuesday, June 1, 2021
 
subroutines
answered 7 Months ago
35

String concatenation is done with + so Javascript will convert the first numeric 1 to a string and concatenate "1" and "1" making "11".

You cannot perform subtraction on strings, so Javascript converts the second "1" to a number and subtracts 1 from 1, resulting in zero.

Tuesday, June 1, 2021
 
LoicTheAztec
answered 7 Months ago
48

There're two versions of ShareActionProvider, the android framework's and the v7 support library's.

In Sunshine you need to support min SDK version 10, while ShareActionProvider was added into the framework from API level 14, so how to provide the feature to SDK 10-13? You use the support library version instead.

You import the support library in build.gradle here

dependencies {
    ...
    compile 'com.android.support:appcompat-v7:21.0.2'
}

Now back to your question about the app namespace. Sunshine is using the attributes that are not available in the framework on the lower SDKs they support (actionProviderClass and showAsAction), so they need to use the custom attributes provided by the support library, and to use the custom attributes you need to use the app namespace. The android namespace is for the framework attributes as the name suggested.

<?xml version="1.0" encoding="utf-8"?>

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <item android:id="@+id/action_share"
        android:title="@string/action_share"
        app:showAsAction="always"
        app:actionProviderClass="android.support.v7.widget.ShareActionProvider" />
</menu>
Tuesday, September 21, 2021
 
srinivas p
answered 3 Months ago
69

I was able to fix this issue by making browser sleep for few seconds after every change in URL.

Below is the code snippet:

67 it('should create new job listing', function () {
68        //Login As Admin To Access Vacancies Feature
69        loginAsManager();
.
.        //load manager's dashboard list page
.        dashboardPage = new DashboardPage();
.        dashboardPage.vacanciesTab.click();
.
.        //load vacancies list page
.        var vacanciesUrl = browser.baseUrl + '#/vacancies';
.        browser.sleep(2000);
.        expect(browser.getCurrentUrl()).toEqual(vacanciesUrl);
.        vacanciesPage = new VacanciesPage();
.        vacanciesPage.addVacancyButton.click();
.
.

I don't think this is a neat solution to this problem.

I will be happy to hear, if someone has a better solution to this.

Cheers Gaurav

Friday, October 15, 2021
 
Morrison Chang
answered 2 Months ago
94

Maybe a dependency error. I'll suggest you to use a better practice for such lib.

  1. Put the fullcalendar scripts into vendor/assets/javascripts

  2. Require this script manually in application.js before the tree and after jquery and any other lib it depends.

    /=require 'fullcalendar`
    

Add

Check the loaded Javascript files in header, if application.js is the last, you have dependency error. The lib must be there before calling it.

Thursday, November 11, 2021
 
Yuriy Faktorovich
answered 3 Weeks ago
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