Typescript const enum vs enum ([email protected])

const-enum.ts

// Declare
const enum CommandType {
    FOO = 1,
    BAR = 2
};

// Usage
const commandType = CommandType.FOO

// Transpiled (inlining)
var commandType = 1

enum.ts

// Declare
enum CommandType {
    FOO = 1,
    BAR = 2
};

// Usage
const commandType = CommandType.FOO

// Transpiled (still referenced)
var commandType = CommandType.FOO

// Behind the schenes
var CommandType;
(function (CommandType) {
    CommandType[CommandType["FOO"] = 1] = "FOO";
    CommandType[CommandType["BAR"] = 2] = "BAR";
})(CommandType = {}));