# micromark-extension-gfm-table [![Build][build-badge]][build] [![Coverage][coverage-badge]][coverage] [![Downloads][downloads-badge]][downloads] [![Size][size-badge]][size] [![Sponsors][sponsors-badge]][collective] [![Backers][backers-badge]][collective] [![Chat][chat-badge]][chat] [micromark][] extensions to support GFM [tables][]. ## Contents * [What is this?](#what-is-this) * [When to use this](#when-to-use-this) * [Install](#install) * [Use](#use) * [API](#api) * [`gfmTable()`](#gfmtable) * [`gfmTableHtml()`](#gfmtablehtml) * [Bugs](#bugs) * [Authoring](#authoring) * [HTML](#html) * [CSS](#css) * [Syntax](#syntax) * [Types](#types) * [Compatibility](#compatibility) * [Security](#security) * [Related](#related) * [Contribute](#contribute) * [License](#license) ## What is this? This package contains extensions that add support for the table syntax enabled by GFM to [`micromark`][micromark]. These extensions match github.com. ## When to use this This project is useful when you want to support tables in markdown. You can use these extensions when you are working with [`micromark`][micromark]. To support all GFM features, use [`micromark-extension-gfm`][micromark-extension-gfm] instead. When you need a syntax tree, combine this package with [`mdast-util-gfm-table`][mdast-util-gfm-table]. All these packages are used in [`remark-gfm`][remark-gfm], which focusses on making it easier to transform content by abstracting these internals away. ## Install This package is [ESM only][esm]. In Node.js (version 16+), install with [npm][]: ```sh npm install micromark-extension-gfm-table ``` In Deno with [`esm.sh`][esmsh]: ```js import {gfmTable, gfmTableHtml} from 'https://esm.sh/micromark-extension-gfm-table@2' ``` In browsers with [`esm.sh`][esmsh]: ```html ``` ## Use ```js import {micromark} from 'micromark' import {gfmTable, gfmTableHtml} from 'micromark-extension-gfm-table' const output = micromark('| a |\n| - |', { extensions: [gfmTable()], htmlExtensions: [gfmTableHtml()] }) console.log(output) ``` Yields: ```html

a

``` ## API This package exports the identifiers [`gfmTable`][api-gfm-table] and [`gfmTableHtml`][api-gfm-table-html]. There is no default export. The export map supports the [`development` condition][development]. Run `node --conditions development module.js` to get instrumented dev code. Without this condition, production code is loaded. ### `gfmTable()` Create an HTML extension for `micromark` to support GitHub tables syntax. ###### Returns Extension for `micromark` that can be passed in `extensions` to enable GFM table syntax ([`Extension`][micromark-extension]). ### `gfmTableHtml()` Create an HTML extension for `micromark` to support GitHub tables when serializing to HTML. ###### Returns Extension for `micromark` that can be passed in `htmlExtensions` to support GFM tables when serializing to HTML ([`HtmlExtension`][micromark-html-extension]). ## Bugs GitHub’s own algorithm to parse tables contains a bug. This bug is not present in this project. The issue relating to tables is: * [GFM tables: escaped escapes are incorrectly treated as escapes](https://github.com/github/cmark-gfm/issues/277) ## Authoring When authoring markdown with GFM tables, it’s recommended to *always* put pipes around cells. Without them, it can be hard to infer whether the table will work, how many columns there are, and which column you are currently editing. It is recommended to not use many columns, as it results in very long lines, making it hard to infer which column you are currently editing. For larger tables, particularly when cells vary in size, it is recommended *not* to manually “pad” cell text. While it can look better, it results in a lot of time spent realigning everything when a new, longer cell is added or the longest cell removed, as every row then must be changed. Other than costing time, it also causes large diffs in Git. To illustrate, when authoring large tables, it is discouraged to pad cells like this: ```markdown | Alpha bravo charlie | delta | | ------------------- | -----------------: | | Echo | Foxtrot golf hotel | ``` Instead, use single spaces (and single filler dashes): ```markdown | Alpha bravo charlie | delta | | - | -: | | Echo | Foxtrot golf hotel | ``` ## HTML GFM tables relate to several HTML elements: ``, ``, ``, and ``. See [*§ 4.9.1 The `table` element*][html-table], [*§ 4.9.5 The `tbody` element*][html-tbody], [*§ 4.9.9 The `td` element*][html-td], [*§ 4.9.10 The `th` element*][html-th], [*§ 4.9.6 The `thead` element*][html-thead], and [*§ 4.9.8 The `tr` element*][html-tr] in the HTML spec for more info. If the alignment of a column is left, right, or center, a deprecated `align` attribute is added to each `

`, ` `, `

` and `

` element belonging to that column. That attribute is interpreted by browsers as if a CSS `text-align` property was included, with its value set to that same keyword. ## CSS The following CSS is needed to make tables look a bit like GitHub. For the complete actual CSS see [`sindresorhus/github-markdown-css`][github-markdown-css] ```css /* Light theme. */ :root { --color-canvas-default: #ffffff; --color-canvas-subtle: #f6f8fa; --color-border-default: #d0d7de; --color-border-muted: hsla(210, 18%, 87%, 1); } /* Dark theme. */ @media (prefers-color-scheme: dark) { :root { --color-canvas-default: #0d1117; --color-canvas-subtle: #161b22; --color-border-default: #30363d; --color-border-muted: #21262d; } } table { border-spacing: 0; border-collapse: collapse; display: block; margin-top: 0; margin-bottom: 16px; width: max-content; max-width: 100%; overflow: auto; } tr { background-color: var(--color-canvas-default); border-top: 1px solid var(--color-border-muted); } tr:nth-child(2n) { background-color: var(--color-canvas-subtle); } td, th { padding: 6px 13px; border: 1px solid var(--color-border-default); } th { font-weight: 600; } table img { background-color: transparent; } ``` ## Syntax Tables form with the following BNF: ```abnf gfmTable ::= gfmTableHead 0*(eol gfmTableBodyRow) ; Restriction: both rows must have the same number of cells. gfmTableHead ::= gfmTableRow eol gfmTableDelimiterRow gfmTableRow ::= ["|"] gfmTableCell 0*("|" gfmTableCell) ["|"] *spaceOrTab gfmTableCell ::= *spaceOrTab gfmTableText *spaceOrTab gfmTableText ::= 0*(line - "\\" - "|" / "\\" ["\\" / "|"]) gfmTableDelimiterRow ::= ["|"] gfmTableDelimiterCell 0*("|" gfmTableDelimiterCell) ["|"] *spaceOrTab gfmTableDelimiterCell ::= *spaceOrTab gfmTableDelimiterValue *spaceOrTab gfmTableDelimiterValue ::= [":"] 1*"-" [":"] ``` As this construct occurs in flow, like all flow constructs, it must be followed by an eol (line ending) or eof (end of file). The above grammar shows that basically anything can be a cell or a row. The main thing that makes something a row, is that it occurs directly before or after a delimiter row, or after another row. It is not required for a table to have a body: it can end right after the delimiter row. Each column can be marked with an alignment. The alignment marker is a colon (`:`) used before and/or after delimiter row filler. To illustrate: ```markdown | none | left | right | center | | ---- | :--- | ----: | :----: | ``` The number of cells in the delimiter row, is the number of columns of the table. Only the head row is required to have the same number of cells. Body rows are not required to have a certain number of cells. For body rows that have less cells than the number of columns of the table, empty cells are injected. When a row has more cells than the number of columns of the table, the superfluous cells are dropped. To illustrate: ```markdown | a | b | | - | - | | c | | d | e | f | ``` Yields: ```html

a	b
c
d	e

``` Each cell’s text is interpreted as the [text][micromark-content-type] content type. That means that it can include constructs such as attention (emphasis, strong). The grammar for cells prohibits the use of `|` in them. To use pipes in cells, encode them as a character reference or character escape: `|` (or `|`, `|`, `|`, `|`) or `\|`. Escapes will typically work, but they are not supported in code (text) (and the math (text) extension). To work around this, GitHub came up with a rather weird “trick”. When inside a table cell *and* inside code, escaped pipes *are* decoded. To illustrate: ```markdown | Name | Character | | - | - | | Left curly brace | `{` | | Pipe | `\|` | | Right curly brace | `}` | ``` Yields: ```html

Name	Character
Left curly brace	`{`
Pipe	`\|`
Right curly brace	`}`

``` > 👉 **Note**: no other character can be escaped like this. > Escaping pipes in code does not work when not inside a table, either. ## Types This package is fully typed with [TypeScript][]. It exports no additional types. ## Compatibility Projects maintained by the unified collective are compatible with maintained versions of Node.js. When we cut a new major release, we drop support for unmaintained versions of Node. This means we try to keep the current release line, `micromark-extension-gfm-table@^2`, compatible with Node.js 16. This package works with `micromark` version `3` and later. ## Security This package is safe. ## Related * [`micromark-extension-gfm`][micromark-extension-gfm] — support all of GFM * [`mdast-util-gfm-table`][mdast-util-gfm-table] — support all of GFM in mdast * [`mdast-util-gfm`][mdast-util-gfm] — support all of GFM in mdast * [`remark-gfm`][remark-gfm] — support all of GFM in remark ## Contribute See [`contributing.md` in `micromark/.github`][contributing] for ways to get started. See [`support.md`][support] for ways to get help. This project has a [code of conduct][coc]. By interacting with this repository, organization, or community you agree to abide by its terms. ## License [MIT][license] © [Titus Wormer][author] [build-badge]: https://github.com/micromark/micromark-extension-gfm-table/workflows/main/badge.svg [build]: https://github.com/micromark/micromark-extension-gfm-table/actions [coverage-badge]: https://img.shields.io/codecov/c/github/micromark/micromark-extension-gfm-table.svg [coverage]: https://codecov.io/github/micromark/micromark-extension-gfm-table [downloads-badge]: https://img.shields.io/npm/dm/micromark-extension-gfm-table.svg [downloads]: https://www.npmjs.com/package/micromark-extension-gfm-table [size-badge]: https://img.shields.io/badge/dynamic/json?label=minzipped%20size&query=$.size.compressedSize&url=https://deno.bundlejs.com/?q=micromark-extension-gfm-table [size]: https://bundlejs.com/?q=micromark-extension-gfm-table [sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg [backers-badge]: https://opencollective.com/unified/backers/badge.svg [collective]: https://opencollective.com/unified [chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg [chat]: https://github.com/micromark/micromark/discussions [npm]: https://docs.npmjs.com/cli/install [esmsh]: https://esm.sh [license]: license [author]: https://wooorm.com [contributing]: https://github.com/micromark/.github/blob/main/contributing.md [support]: https://github.com/micromark/.github/blob/main/support.md [coc]: https://github.com/micromark/.github/blob/main/code-of-conduct.md [esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c [typescript]: https://www.typescriptlang.org [development]: https://nodejs.org/api/packages.html#packages_resolving_user_conditions [micromark]: https://github.com/micromark/micromark [micromark-extension]: https://github.com/micromark/micromark#syntaxextension [micromark-html-extension]: https://github.com/micromark/micromark#htmlextension [micromark-content-type]: https://github.com/micromark/micromark#content-types [micromark-extension-gfm]: https://github.com/micromark/micromark-extension-gfm [mdast-util-gfm]: https://github.com/syntax-tree/mdast-util-gfm [mdast-util-gfm-table]: https://github.com/syntax-tree/mdast-util-gfm-table [remark-gfm]: https://github.com/remarkjs/remark-gfm [tables]: https://github.github.com/gfm/#tables-extension- [html-table]: https://html.spec.whatwg.org/multipage/tables.html#the-table-element [html-tbody]: https://html.spec.whatwg.org/multipage/tables.html#the-tbody-element [html-thead]: https://html.spec.whatwg.org/multipage/tables.html#the-thead-element [html-tr]: https://html.spec.whatwg.org/multipage/tables.html#the-tr-element [html-td]: https://html.spec.whatwg.org/multipage/tables.html#the-td-element [html-th]: https://html.spec.whatwg.org/multipage/tables.html#the-th-element [github-markdown-css]: https://github.com/sindresorhus/github-markdown-css [api-gfm-table]: #gfmtable [api-gfm-table-html]: #gfmtablehtml

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zip	dev/	38113	14	---	2026-09-25 16:03:30
zip	lib/	34795	12	---	2026-09-25 16:03:30
-	index.d.ts	1273		ts	2026-09-25 16:03:30
-	index.js	89		js	2026-09-25 16:03:30
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🌲 / foundry13data Data modules tidy-ui_game-settings node_modules micromark-extension-gfm-table

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