pegjs/pegjs

### Issue type

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- **Bug Report:** 
- **Feature Request:** 
- **Question:** 
- **Not an issue:** 

### Prerequisites

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- **Can you reproduce the issue?:** 
- **Did you search the repository issues?:** 
- **Did you check the forums?:** 
- **Did you perform a web search (google, yahoo, etc)?:** 

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### Description

<!-- A description of the bug, feature or question -->

### Steps to Reproduce

1. <!-- First Step -->
2. <!-- Second Step -->
3. <!-- and so on... -->

**Example code:**

```js
  // An example of code related to this issue
```

**Expected behavior:**

<!-- What you expected to happen -->

**Actual behavior:**

<!-- What actually happened -->

### Software

<!-- Having more details about your software might help pinpoint the source of a bug: -->

- **PEG.js:** 
- **Node.js:** 
- **NPM or Yarn:** 
- **Browser:** 
- **OS:** 
- **Editor:**