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ES6 Set & Map

Map & Set

https://github.com/xgqfrms/RAIO/issues/167

ES6 Map

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map

const arr = [
    "INNERCODE", "SECUCODE", "SECUABBR", "TRADINGDAY", "LASTWEEKTRADINGDAY", "CLOSEPRICE", "CHANGE", "CHANGERANGE",
    "INNERCODE", "SECUCODE", "SECUABBR", "TRADINGDAY", "LASTWEEKTRADINGDAY", "CLOSEPRICE", "CHANGE", "CHANGERANGE",
];

let map_arr = new Map(arr);
// Uncaught TypeError: Iterator value INNERCODE is not an entry object at new Map (<anonymous>)

let set_arr = new Set(arr);
// Set(8) {"INNERCODE", "SECUCODE", "SECUABBR", "TRADINGDAY", "LASTWEEKTRADINGDAY", …}

let new_arr = [...set_arr];
// (8) ["INNERCODE", "SECUCODE", "SECUABBR", "TRADINGDAY", "LASTWEEKTRADINGDAY", "CLOSEPRICE", "CHANGE", "CHANGERANGE"]

ES6 Set

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set

let mySet = new Set();

mySet.add(1); 
// Set [ 1 ]

mySet.add(5); 
// Set [ 1, 5 ]

mySet.add(5);
 // Set [ 1, 5 ]

mySet.add('some text');
// Set [ 1, 5, 'some text' ]

setter

setter - JavaScript | MDN

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/set

Set

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set

const set1 = new Set([1, 2, 3, 4, 5]);

console.log(set1.has(1));
// expected output: true

console.log(set1.has(7));
// expected output: false

console.log(set1.add(7));
// expected output: true

console.log(set1.has(7));
// expected output: true

console.log(set1.has(6));
// expected output: false

refs

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