Equality (समानता)

Programmers frequently need to determine the equality of variables in relation to other variables. This is done using an equality operator.

प्रोग्रामरहरूमा भ्यारीएबलहरूको सम्बन्धमा समानता निर्धारण गर्नुपर्दछ। यो समानता निर्धारण गर्न समानता अपरेटर प्रयोग गरेर गरिन्छ।

The most basic equality operator is the == operator. This operator does everything it can to determine if two variables are equal, even if they are not of the same type.

सब भन्दा आधारभूत अपरेटर समानता अपरेटर (==) हो। यस अपरेटरले यो निर्धारण गर्दछ कि दुई भ्यारीएबल बराबर छ कि छैन।

For example, assume:

let foo = 42;
let bar = 42;
let baz = "42";
let qux = "life";

foo == bar will evaluate to true and baz == qux will evaluate to false, as one would expect. However, foo == baz will also evaluate to true despite foo and baz being different types. Behind the scenes the == equality operator attempts to force its operands to the same type before determining their equality. This is in contrast to the === equality operator.

foo == bar को मूल्यांकन गर्दा साँचो र baz == qux को लागी झूटा को मूल्यांकन हुनेछ।foo र Bazबिभिन्न प्रकारका बावजुद foo == bazको मूल्यांकन साँचो हुनेछ। दृश्यहरूको पछाडि == समानता अपरेटरले आफ्नो समानता निर्धारण गर्नु अघि यसको प्रकारलाई अपरेट गर्दछ। यो === समानता अपरेटरको विपरित हो।

The === equality operator determines that two variables are equal if they are of the same type and have the same value. With the same assumptions as before, this means that foo === bar will still evaluate to true, but foo === baz will now evaluate to false. baz === qux will still evaluate to false.

इकुअलिटी अपरेटरले (===) दुई भ्यारीएबल बराबर र समान प्रकारका छन् भन्ने निर्धारण गर्दछ ।

let str1 = "hello";
let str2 = "HELLO";
let bool1 = true;
let bool2 = 1;
// compare using ==
let stringResult1 = str1 == str2 // false
let boolResult1 =  bool1 == bool2 // true

// compare using ===
let stringResult2 = str1 === str2 // false
let boolResult2 = bool1 === bool2 // false

assert(stringResult1 === false && stringResult2 === false && boolResult1 ==true &&  boolResult2 === false );