去重的hashset类似

mySet: Set<string> = new Set<string>();

const mySet1 = new Set()

mySet1.add(1) // Set [ 1 ]
mySet1.add(5) // Set [ 1, 5 ]
mySet1.add(5) // Set [ 1, 5 ]
mySet1.add('some text') // Set [ 1, 5, 'some text' ]
const o = {a: 1, b: 2}
mySet1.add(o)

mySet1.add({a: 1, b: 2}) // o is referencing a different object, so this is okay

mySet1.has(1) // true
mySet1.has(3) // false, since 3 has not been added to the set
mySet1.has(5) // true
mySet1.has(Math.sqrt(25)) // true
mySet1.has('Some Text'.toLowerCase()) // true
mySet1.has(o) // true

mySet1.size // 5

mySet1.delete(5) // removes 5 from the set
mySet1.has(5) // false, 5 has been removed

mySet1.size // 4, since we just removed one value

console.log(mySet1)