Primitive Type ( → Primitive Values)
- 변수에 실질적인 값이 그대로 할당된 타입
- 가용 가능한 허용 메모리 내에 실제 값이 저장된다.
☞ Number Type
value1 = 10; // 10
value2 = 5.5; // 5.5
value3 = 1000; // 1000
value4 = 365.123; // 365.123
maxValue = Number.MAX_VALUE; // 1.7976931348623157e+308
minValue = Number.MIN_VALUE; // 5e-324
console.log(typeof(value1)); // number
console.log(typeof(value2)); // number
console.log(typeof(value3)); // number
console.log(typeof(value4)); // number
☞ Boolean Type
let boolTrue = true;
let boolFalse = false;
let boolTrueWrapper = new Boolean(true);
let boolFalseWrapper = new Boolean(false);
console.log(boolTrue); // true
console.log(boolFalse); // false
console.log(boolTrueWrapper.valueOf()); // true
console.log(boolFalseWrapper.valueOf()); // false
console.log(typeof(boolTrue)); // boolean
console.log(typeof(boolFalse)); // boolean
console.log(typeof(boolTrueWrapper)); // object
console.log(typeof(boolFalseWrapper)); // object
☞ String Type
let movie1 = "movie1"; // movie1
let movie2 = 'movie2'; // movie2
let movie3 = `movie3`; // movie3
console.log(typeof(movie1)); // string
console.log(typeof(movie2)); // string
console.log(typeof(movie3)); // string
let tom = new String("tom");
console.log(tom); // String{"tom"}
console.log(tom.valueOf()); // tom
console.log(tom[0]); // t
console.log(tom[1]); // o
console.log(tom[2]); // m
let ABCDE = "ABCDE";
console.log(ABCDE.charAt(3)); // D
☞ Null Type ★
let nullValue = null;
console.log(nullValue); // null
console.log(nullValue === undefined) // false
console.log(nullValue === null); // true
☞ Undefined Type ★
let value;
console.log(value); // undefinded
let jump = undefined;
console.log(jump); // undefinded
jump === undefined; // true
jump === null; // false
reference
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