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schangxiang@126.com

2025-09-19 18966e02fb573c7e2bb0c6426ed792b38b910940

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# babel-plugin-transform-es2015-typeof-symbol
 
> ES6 introduces a new native type called [symbols](https://babeljs.io/learn-es2015/#ecmascript-2015-features-symbols). This transformer wraps all `typeof` expressions with a method that replicates native behaviour. (ie. returning "symbol" for symbols)
 
## Example
 
**In**
 
```javascript
typeof Symbol() === "symbol";
```
 
**Out**
 
```javascript
var _typeof = function (obj) {
  return obj && obj.constructor === Symbol ? "symbol" : typeof obj;
};
 
_typeof(Symbol()) === "symbol";
```
 
## Installation
 
```sh
npm install --save-dev babel-plugin-transform-es2015-typeof-symbol
```
 
## Usage
 
### Via `.babelrc` (Recommended)
 
**.babelrc**
 
```json
{
  "plugins": ["transform-es2015-typeof-symbol"]
}
```
 
### Via CLI
 
```sh
babel --plugins transform-es2015-typeof-symbol script.js
```
 
### Via Node API
 
```javascript
require("babel-core").transform("code", {
  plugins: ["transform-es2015-typeof-symbol"]
});
```