### Install mdast-util-gfm with npm

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

Install the mdast-util-gfm package using npm for Node.js environments. This command fetches and installs the package and its dependencies.

```sh
npm install mdast-util-gfm
```

--------------------------------

### GFM Autolink Literals, Footnotes, Strikethrough, Tables, Tasklists (Markdown)

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

This is a sample Markdown document showcasing various GitHub Flavored Markdown (GFM) features that can be processed by `mdast-util-gfm`. It includes autolink literals, footnotes, strikethrough text, tables, and tasklists.

```markdown
# GFM

## Autolink literals

[www.example.com](http://www.example.com), <https://example.com>, and <contact@example.com>.

## Footnote

A note[^1]

[^1]: Big note.

## Strikethrough

~~one~~ or ~~two~~ tildes.

## Table

| a | b  |  c |  d  |
| - | :- | -: | :-: |

## Tasklist

*   [ ] to do
*   [x] done
```

--------------------------------

### Import mdast-util-gfm in Deno

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

Import the gfmFromMarkdown and gfmToMarkdown functions from mdast-util-gfm in Deno using esm.sh. This allows direct use in Deno projects.

```javascript
import {gfmFromMarkdown, gfmToMarkdown} from 'https://esm.sh/mdast-util-gfm@3'
```

--------------------------------

### Import mdast-util-gfm in Browser

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

Import the gfmFromMarkdown and gfmToMarkdown functions from mdast-util-gfm in the browser using esm.sh with bundling enabled. This provides the functions as a module for browser-based JavaScript.

```html
<script type="module">
  import {gfmFromMarkdown, gfmToMarkdown} from 'https://esm.sh/mdast-util-gfm@3?bundle'
</script>
```

--------------------------------

### Parse Markdown with GFM extensions (JavaScript)

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

This snippet demonstrates how to use `mdast-util-gfm` to parse a Markdown string into an mdast tree, enabling GFM features. It utilizes `fs` for file reading, `fromMarkdown` from `mdast-util-from-markdown`, and GFM extensions. The resulting AST is logged to the console.

```javascript
import fs from 'node:fs/promises'
import {fromMarkdown} from 'mdast-util-from-markdown'
import {gfmFromMarkdown, gfmToMarkdown} from 'mdast-util-gfm'
import {toMarkdown} from 'mdast-util-to-markdown'
import {gfm} from 'micromark-extension-gfm'

const value = await fs.readFile('example.md', 'utf8')

const tree = fromMarkdown(value, {
  extensions: [gfm()],
  mdastExtensions: [gfmFromMarkdown()]
})

console.log(tree)

const result = toMarkdown(tree, {extensions: [gfmToMarkdown()]})

console.log(result)
```

--------------------------------

### GFM Parsing and Serialization API

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

This section details the functions for enabling GitHub Flavored Markdown (GFM) parsing and serialization with mdast.

```APIDOC
## API

This package exports the identifiers [`gfmFromMarkdown`][api-gfm-from-markdown]
and [`gfmToMarkdown`][api-gfm-to-markdown].
There is no default export.

### `gfmFromMarkdown()`

Create an extension for [`mdast-util-from-markdown`][mdast-util-from-markdown]
to enable GFM (autolink literals, footnotes, strikethrough, tables, tasklists).

###### Returns

Extension for `mdast-util-from-markdown` to enable GFM
([`Array<FromMarkdownExtension>`][from-markdown-extension]).

### `gfmToMarkdown(options?)`

Create an extension for [`mdast-util-to-markdown`][mdast-util-to-markdown]
to enable GFM (autolink literals, footnotes, strikethrough, tables, tasklists).

###### Parameters

* `options` ([`Options`][api-options])
  — configuration

###### Returns

Extension for `mdast-util-to-markdown` to enable GFM
([`Array<ToMarkdownExtension>`][to-markdown-extension]).

### `Options`

Configuration (TypeScript type).

```

--------------------------------

### Configure GFM table cell padding and alignment

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

This utility provides options to control how table delimiters are handled. `tableCellPadding` adds spaces around cell content, and `tablePipeAlign` ensures consistent alignment of pipe characters in table syntax. These options affect the parsing and potentially the representation of table nodes in the AST.

```javascript
import {mdastUtilGfm} from 'mdast-util-gfm';

// Example usage with options:
const processor = unified()
  .use(markdown)
  .use(mdastUtilGfm, {
    tableCellPadding: true,
    tablePipeAlign: false,
  });

```

--------------------------------

### Configure GFM first line blank footnote definitions

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

The `firstLineBlank` option in `mdast-util-gfm` determines whether a blank line is required before the first line of a footnote definition. This setting influences how footnote definitions are parsed and recognized within the markdown AST, impacting the interpretation of footnote content.

```javascript
import {mdastUtilGfm} from 'mdast-util-gfm';

// Example usage with firstLineBlank option:
const processor = unified()
  .use(markdown)
  .use(mdastUtilGfm, {
    firstLineBlank: true,
  });

```

--------------------------------

### Configure GFM table cell content length detection

Source: https://github.com/syntax-tree/mdast-util-gfm/blob/main/readme.md

The `stringLength` option allows customization of how the length of table cell content is detected. This function is crucial for aligning delimiters between table cells, ensuring consistent formatting. Providing a custom function can be useful for handling complex cell content or specific display requirements.

```javascript
import {mdastUtilGfm} from 'mdast-util-gfm';

// Example usage with custom stringLength function:
const processor = unified()
  .use(markdown)
  .use(mdastUtilGfm, {
    stringLength: (value) => value.split('').filter(char => char !== ' ').length, // Example: count non-space characters
  });

```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.