54 lines
960 B
Markdown
54 lines
960 B
Markdown
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# babel-plugin-transform-es2015-typeof-symbol
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> 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)
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## Example
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**In**
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```javascript
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typeof Symbol() === "symbol";
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```
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**Out**
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```javascript
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var _typeof = function (obj) {
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return obj && obj.constructor === Symbol ? "symbol" : typeof obj;
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};
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_typeof(Symbol()) === "symbol";
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```
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## Installation
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```sh
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npm install --save-dev babel-plugin-transform-es2015-typeof-symbol
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```
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## Usage
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### Via `.babelrc` (Recommended)
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**.babelrc**
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```json
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{
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"plugins": ["transform-es2015-typeof-symbol"]
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}
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```
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### Via CLI
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```sh
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babel --plugins transform-es2015-typeof-symbol script.js
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```
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### Via Node API
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```javascript
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require("babel-core").transform("code", {
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plugins: ["transform-es2015-typeof-symbol"]
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});
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```
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