array-treeify/README.md

Simple text tree diagrams from arrays.

# 🪾 `array-treeify`

**Simple text trees from arrays using Unicode box-drawing characters. For your terminal and console displays.**

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## Overview

`array-treeify` transforms nested arrays into text trees with proper branching characters. Perfect for CLIs, debug outputs, or anywhere you need to visualize hierarchical data.

```typescript
treeify([
  'Lumon Industries',
  [
    'Board of Directors',
    ['Natalie (Representative)'],
    'Departments',
    [
      'Macrodata Refinement (Cobel)',
      ['Milchick', 'Mark S.', ['Dylan G.', 'Irving B.', 'Helly R.']],
    ],
    'Other Departments',
    [
      'Optics & Design',
      'Wellness Center',
      'Mammalians Nurturable',
      'Choreography and Merriment',
    ],
  ],
])
```


```
Lumon Industries
├─ Board of Directors
│  └─ Natalie (Representative)
├─ Departments
│  └─ Macrodata Refinement (Cobel)
│     ├─ Milchick
│     └─ Mark S.
│        ├─ Dylan G.
│        ├─ Irving B.
│        └─ Helly R.
└─ Other Departments
   ├─ Optics & Design
   ├─ Wellness Center
   ├─ Mammalians Nurturable
   └─ Choreography and Merriment
```

## Installation

```bash
npm install array-treeify
```

## Usage

```typescript
function treeify(input: TreeInput, options?: {
  chars?: TreeChars,  // Custom characters for the tree
  plain?: boolean     // Use plain whitespace instead of Unicode box-drawing characters
}): string
```

`array-treeify` accepts a simple, intuitive array structure that's easy to build and manipulate:

```typescript
import {treeify} from 'array-treeify'

// Basic example
const eagan = [
  'Kier Eagan', 
  [
    '...',
    [
      '...',
      'Jame Eagan',
      ['Helena Eagan']
    ],
    'Ambrose Eagan',
  ],
]
console.log(treeify(eagan))
/*
Kier Eagan
├─ ...
│  ├─ ...
│  └─ Jame Eagan
│     └─ Helena Eagan
└─ Ambrose Eagan
*/

// Using custom characters
const resultCustomChars = treeify(
  eagan, 
  { chars: { branch: '├• ', lastBranch: '└• ', pipe: '│  ', space: '   ' },
})
/*
Kier Eagan
├• ...
│  ├• ...
│  └• Jame Eagan
│     └• Helena Eagan
└• Ambrose Eagan
*/

// Using plain whitespace characters
console.log(treeify(eagan, { plain: true }))
/*
Kier Eagan
   ...
      ...
      Jame Eagan
         Helena Eagan
   Ambrose Eagan
*/

// Nested example
const orgChart = [
  'Lumon Industries',
  [
    'Board of Directors',
    ['Natalie (Representative)'],
    'Department Heads',
    [
      'Cobel (MDR)',
      ['Milchick', 'Mark S.', ['Dylan G.', 'Irving B.', 'Helly R.']]
    ]
  ]
]
console.log(treeify(orgChart))
/*
Lumon Industries
├─ Board of Directors
│  └─ Natalie (Representative)
└─ Department Heads
   └─ Cobel (MDR)
      ├─ Milchick
      └─ Mark S.
         ├─ Dylan G.
         ├─ Irving B.
         └─ Helly R.
*/
```

## Input Format

> **Disclaimer:**
> The exported `TreeInput` type (`Array<string | TreeInput>`) is intentionally flexible to support dynamic and programmatic tree construction. However, TypeScript cannot enforce at the type level that the first element is a string. This requirement is checked at runtime by the `treeify` function, which will throw an error if the first element is not a string. Please ensure your input arrays follow this convention.

The `treeify` function accepts arrays with the following structure:

1. First element must be a string (the root node)
2. Subsequent elements can be strings (nodes at same level) or arrays (children of previous node)
3. Arrays can be nested to any depth

```typescript
['root', 'sibling', ['child1', 'child2']]             // Root with 2 children
['root', ['child'], 'sibling', ['nephew', 'niece']]   // 2 root nodes with children
['root', ['child', ['grandchild']]]                   // Grandchildren
```

## Options

- `chars`: Custom characters for the tree. Defaults to Unicode box-drawing characters.
- `plain`: When true, uses plain whitespace characters instead of Unicode box-drawing characters.

## License

MIT © tbeseda