LOWDOWN(3)

💖 LOWDOWN(3) — simple markdown translator library ✨

okay bestie, welcome to the lowdown(3) page. This is the library that parses lowdown(5) into a bunch of different output formats, and we're gonna get you comfy with it. No cap.

🌸 NAME

lowdown — simple markdown translator library

📚 LIBRARY

library “liblowdown”

🧚 SYNOPSIS

#include <sys/queue.h>
#include <stdio.h>
#include <lowdown.h>

struct lowdown_meta
struct lowdown_node
struct lowdown_opts

💅 DESCRIPTION

This library parses lowdown(5) into various output formats. Slay.

The library starts with a high-level interface made of lowdown_buf(3), lowdown_buf_diff(3), lowdown_file(3), and lowdown_file_diff(3).

Those high-level functions talk to low-level functions that do the actual parsing and formatting. The low-level crew is lowdown_doc_new(3), lowdown_doc_parse(3), and lowdown_doc_free(3), and they're what turn lowdown(5) documents into an abstract syntax tree.

The front-end functions for freeing, allocation, and rendering are literally these:

• HTML5: lowdown_html_free(3), lowdown_html_new(3), lowdown_html_rndr(3)
• gemini: lowdown_gemini_free(3), lowdown_gemini_new(3), lowdown_gemini_rndr(3)
• LaTeX: lowdown_latex_free(3), lowdown_latex_new(3), lowdown_latex_rndr(3)
• OpenDocument: lowdown_odt_free(3), lowdown_odt_new(3), lowdown_odt_rndr(3)
• roff: lowdown_roff_free(3), lowdown_roff_new(3), lowdown_roff_rndr(3)
• UTF-8 ANSI terminal: lowdown_term_free(3), lowdown_term_new(3), lowdown_term_rndr(3)
• debugging: lowdown_tree_rndr(3)

To compile and link, use pkg-config(1):

% cc `pkg-config --cflags lowdown` -c -o sample.o sample.c
% cc -o sample sample.o `pkg-config --libs lowdown`

🛡️ Pledge Promises

The lowdown library is built to operate in security-sensitive environments, like the ones using pledge(2) on OpenBSD. The only promise required is stdio for lowdown_file_diff(3) and lowdown_file(3): both need access to the stream for reading input. That's it, bestie.

🦋 TYPES

All lowdown functions use one or more of the following structures.

The main structure for configuring parsing and output is struct lowdown_opts. It has the following fields:

• enum lowdown_type type — The output medium:
  • LOWDOWN_HTML — HTML5
  • LOWDOWN_LATEX — LaTeX
  • LOWDOWN_MAN — roff -man macros
  • LOWDOWN_MDOC — roff -mdoc macros
  • LOWDOWN_FODT — “flat” OpenDocument
  • LOWDOWN_TERM — ANSI-compatible UTF-8 terminal output
  • LOWDOWN_GEMINI — Gemini “gemtext” format
  • LOWDOWN_MS — roff -ms macros
  • LOWDOWN_TREE — syntax tree (debugging)
• unsigned int feat — Parse-time features. This bit-field may have the following bits OR'd:
  • LOWDOWN_ATTRS — Parse PHP extra link, header, and image attributes.
  • LOWDOWN_AUTOLINK — Parse http, https, ftp, mailto, and relative links or link fragments.
  • LOWDOWN_CALLOUTS — Parse MDN/GFM callouts (“admonitions”).
  • LOWDOWN_COMMONMARK — Tighten input parsing to the CommonMark specification. Allows for the following features:
    • Using the first ordered list value instead of starting all lists at one.
    • Lists immediately following paragraphs. This feature is experimental and incomplete. iykyk.
  • LOWDOWN_DEFLIST — Parse PHP extra definition lists. This is currently constrained to single-key lists.
  • LOWDOWN_FENCED — Parse GFM fenced (language-specific) code blocks.
  • LOWDOWN_FOOTNOTES — Parse MMD style footnotes. This only supports the referenced footnote style, not the “inline” style.
  • LOWDOWN_HILITE — Parse highlit sequences. These are disabled by default because they may be erroneously interpreted as section headers.
  • LOWDOWN_IMG_EXT — Deprecated. Use LOWDOWN_ATTRS instead.
  • LOWDOWN_MANTITLE — Recognise manpage titles in Pandoc metadata title lines. Only applicable if LOWDOWN_METADATA is also provided. Manpages titles must begin with a non-empty title followed by an open parenthesis, digit or “n”, optional letters after, then a closing parenthesis. This may be optionally followed by a source and, if a vertical bar is detected, the content after as the volume. These are passed to the renderers as the title, volume, and optionally source and volume metadata key-value pairs. The original title is not recoverable.
  • LOWDOWN_MATH — Parse mathematics equations.
  • LOWDOWN_METADATA — Parse in-document metadata.
  • LOWDOWN_NOCODEIND — Do not parse indented content as code blocks.
  • LOWDOWN_NOINTEM — Do not parse emphasis within words.
  • LOWDOWN_STRIKE — Parse strikethrough sequences.
  • LOWDOWN_SUPER — Parse super-scripts. This accepts foo^bar^ GFM super-scripts.
  • LOWDOWN_SUPER_SHORT — If LOWDOWN_SUPER is enabled, instead of the GFM style, accept the “short” form of superscript. This accepts foo^bar, which puts the parts following the caret until whitespace in superscripts; or foo^(bar), which puts only the parts in parenthesis.
  • LOWDOWN_TABLES — Parse GFM tables.
  • LOWDOWN_TASKLIST — Parse GFM task list items.
• unsigned int oflags — Output-time features. Bit values are specific to the type and are not guaranteed to be globally unique.

For all types:

• LOWDOWN_NOLINK — Where possible, don't show links at all. Applies to images and regular links: autolinks are still shown. This may be combined with LOWDOWN_SHORTLINK to also shorten autolinks. Only applies to LOWDOWN_MAN, LOWDOWN_MS, and LOWDOWN_TERM.
• LOWDOWN_NORELLINK — Like LOWDOWN_NOLINK, but only for relative links.
• LOWDOWN_SHORTLINK — Where possible, render link URLs in short form. Applies to images, autolinks, and regular links. This may be combined with LOWDOWN_NOLINK to only show shortened autolinks. Only applies to LOWDOWN_MAN, LOWDOWN_MS, and LOWDOWN_TERM.
• LOWDOWN_SKIP_HTML — Do not render in-document HTML at all. Text within HTML elements remains. Applies to LOWDOWN_HTML, LOWDOWN_FODT, LOWDOWN_LATEX, LOWDOWN_MAN, and LOWDOWN_MS.
• LOWDOWN_SMARTY — Don't use smart typography formatting.
• LOWDOWN_STANDALONE — Emit a full document instead of a document fragment. This envelope is largely populated from metadata if LOWDOWN_METADATA was provided as an option or as given in meta or metaovr.

For LOWDOWN_HTML:

• LOWDOWN_HTML_CALLOUT_MDN, LOWDOWN_HTML_CALLOUT_GFM — Output MDN and/or GFM-style callout syntax.
• LOWDOWN_HTML_CUSTOM_ATTRS — Output unrecognised HTML attributes as well as recognised. For example rel is a recognised HTML attribute, while data-rel is not.
• LOWDOWN_HTML_ESCAPE — If LOWDOWN_SKIP_HTML has not been set, escapes in-document HTML so that it is rendered as opaque text.
• LOWDOWN_HTML_HARD_WRAP — Retain line-breaks within paragraphs.
• LOWDOWN_HTML_HEAD_IDS — Have an identifier written with each header element consisting of an HTML-escaped version of the header contents.
• LOWDOWN_HTML_NUM_ENT — Convert, when possible, HTML entities to their numeric form. If not set, the entities are used as given in the input.
• LOWDOWN_HTML_OWASP — When escaping text, be extra paranoid in following the OWASP suggestions for which characters to escape.
• LOWDOWN_HTML_TITLEBLOCK — Output a Pandoc-style title block. This is a <header id="title-block-header"> element right after the opening <body> containing elements for specified title, author(s), and date. These are <h1> and <p> elements, respectively, with classes set to what's being output (title, etc.). At least one of these must be specified for the title block to be output.

For LOWDOWN_GEMINI, there are several flags for controlling link placement. By default, links (images, autolinks, and links) are queued when specified in-line then emitted in a block sequence after the nearest block node. (See “ABSTRACT SYNTAX TREE”.)

• LOWDOWN_GEMINI_LINK_END — emit the queue of links at the end of the document instead of after the nearest block node. it’s giving “save the link reveal for the finale” 💅
• LOWDOWN_GEMINI_LINK_IN — render all links right within the flow of text. ⚠️ this will cause breakage when nested links happen, like images within links, links in blockquotes, etc. it should not be used unless you’re working with carefully crafted documents, bestie.
• LOWDOWN_GEMINI_LINK_NOREF — do not format link labels. takes precedence over LOWDOWN_GEMINI_LINK_ROMAN.
• LOWDOWN_GEMINI_LINK_ROMAN — when formatting link labels, use lower-case Roman numerals instead of the default lowercase hexavigesimal (i.e., a, b, ..., aa, ab, ...). ✨
• LOWDOWN_GEMINI_METADATA — print metadata as the canonicalised key followed by a colon then the value, each on one line (newlines replaced by spaces). the metadata block is terminated by a double newline. if there is no metadata, this does nothing. 🫶

there may only be one of LOWDOWN_GEMINI_LINK_END or LOWDOWN_GEMINI_LINK_IN. if both are specified, the latter is unset.

for LOWDOWN_FODT, there are no specific flags.

for LOWDOWN_LATEX:

• LOWDOWN_LATEX_NUMBERED — use the default numbering scheme for sections, subsections, etc. if not specified, these are inhibited.

for LOWDOWN_MAN, LOWDOWN_MDOC, and LOWDOWN_MS:

• LOWDOWN_ROFF_GROFF — use GNU extensions (i.e., for groff(1)) when rendering output. the groff arguments must include -mpdfmark for formatting links with LOWDOWN_MAN or -mspdf instead of -ms for LOWDOWN_MS. applies to the LOWDOWN_MAN and LOWDOWN_MS output types.
• LOWDOWN_ROFF_NUMBERED — use numbered sections if LOWDOWON_ROFF_GROFF is not specified. only applies to the LOWDOWN_MS output type.
• LOWDOWN_ROFF_MANPAGE — for LOWDOWN_MAN and LOWDOWN_MDOC, re-format the NAME, SYNOPSIS and SEE ALSO sections to conform to the proper macros for those sections. also interpret font spans in other sections to be manpage-specific, such as command flags and arguments (when in a command manual section) or variables and functions (a function manual section).
• LOWDOWN_ROFF_ENDNOTES — for LOWDOWN_MS, use endnotes instead of footnotes.

for LOWDOWN_TERM:

• LOWDOWN_TERM_ALL_META — if LOWDOWN_STANDALONE is specified, output all metadata instead of just the title, author, and date.
• LOWDOWN_TERM_NOANSI — don’t apply ANSI style codes at all. use backspace encoding instead for bold/underline. this implies LOWDOWN_TERM_NOCOLOUR.
• LOWDOWN_TERM_NOCOLOUR — don’t apply ANSI colour codes. this will still show underline, bold, etc. 🚨 this should not be used in difference mode, as the output will make no sense.
• LOWDOWN_TERM_NOSTYLE — don’t use any escape styles at all. this takes precedence over LOWDOWN_TERM_NOANSI.
• LOWDOWN_TERM_NOTABLEWRAP — don’t wrap table columns to fit the width of the output.

and then there’s the struct field lore:

• size_t maxdepth — the maximum parse depth before the parser exits. most documents will have a parse depth in the single digits.
• struct lowdown_opts_nroff nroff — if type is LOWDOWN_MAN, LOWDOWN_MDOC, or LOWDOWN_MS, this contains constant-width font variants: const char *cr for roman constant-width, const char *cb for bold, const char *ci for italic, and const char *cbi for bold-italic. if any of these are NULL, they default to their constant-width variants.
• struct lowdown_opts_odt odt — if type is LOWDOWN_FODT, this contains const char *sty, which is either NULL or the OpenDocument styles used when creating standalone documents. if NULL, the default styles are used.
• struct lowdown_opts_term term — if type is LOWDOWN_TERM, this contains size_t cols, the non-zero number of columns in the terminal; size_t width, the requested content width or zero for auto; size_t hmargin, left-margin width; size_t hpadding, left-padding width eating into width; size_t vmargin, the vertical margin in lines; and int centre if the content should be centred (hmargin is ignored).
• char **meta — an array of metadata key-value pairs or NULL. each pair must appear as if provided on one line (or multiple lines) of the input, including the terminating newline character. if it isn’t a valid pair (e.g., no newline, no colon), then it is ignored. when processed, these values are overridden by those in the document (if LOWDOWN_METADATA is specified) or by those in metaovr.
• size_t metasz — number of pairs in metaovr.
• char **metaovr — see meta. the difference is that metaovr is applied after meta and in-document metadata, so it overrides prior values.
• size_t metaovrsz — number of pairs in metaovr.
• const char *templ — if LOWDOWN_STANDALONE is specified, this is set to the external template file or NULL to use internal templating. this is only valid for output media supporting external templates; otherwise, it may be ignored.

parsed metadata is held in key-value struct lowdown_meta pairs, or collectively as struct lowdown_metaq, if LOWDOWN_METADATA is set in feat. the former structure consists of the following fields:

• char *key — the metadata key in its canonical form: lowercase alphanumerics, hyphen, and underscore. whitespace is removed and other characters replaced by a question mark.
• char *value — the metadata value. this may be an empty string.

attributes (including extended attributes) for links, headers, and images are held in key-value struct lowdown_attr, which is always specified as a sized array indexed to the enumeration items in enum lowdown_attr_type.

• char *key — if not NULL, the attribute key like class or target. this may be zero-length.
• struct lowdown_buf *value — if not NULL, the attribute value. this may be zero-length.

if the array is non-empty, it will contain at least LOWDOWN_ATTR_CUSTOM buckets for quick indexing. including and following the LOWDOWN_ATTR_CUSTOM bucket are unindexed (unrecognised) attributes. the bucket is valid if its value is not NULL.

the abstract syntax tree is encoded in struct lowdown_node, which consists of the following.

• enum lowdown_rndrt type — the node type, using HTML5 output as an illustration:
• LOWDOWN_BLOCKCODE — a block-level code snippet, described by <pre><code>. 💻
• LOWDOWN_BLOCKHTML — a block-level snippet of HTML. It's literally just opaque HTML content, no cap.
• LOWDOWN_BLOCKQUOTE — a block-level quotation described by <blockquote>. 🫶
• LOWDOWN_CODESPAN — an inline-level snippet of code described by <code>.
• LOWDOWN_DEFINITION — a definition list described by <dl>. ✨
• LOWDOWN_DEFINITION_DATA — definition data described by <dd>.
• LOWDOWN_DEFINITION_TITLE — definition title described by <dt>.
• LOWDOWN_DOC_HEADER — container for metadata described by <head>. 🎀
• LOWDOWN_DOUBLE_EMPHASIS — bold (or otherwise notable) content described by <strong>.
• LOWDOWN_EMPHASIS — italic (or otherwise notable) content described by <em>.
• LOWDOWN_ENTITY — named or numeric HTML entity.
• LOWDOWN_FOOTNOTE — footnote content. 🦋
• LOWDOWN_HEADER — a block-level header described by one of <h1> through <h6>.
• LOWDOWN_HIGHLIGHT — marked text described by <mark>.
• LOWDOWN_HRULE — a horizontal line described by <hr>.
• LOWDOWN_IMAGE — an image described by <img>. 🌸
• LOWDOWN_LINEBREAK — a hard line-break within a block context described by <br>.
• LOWDOWN_LINK — a link to external media described by <a>. Links may contain limited child markup, but not nested links.
• LOWDOWN_LINK_AUTO — like LOWDOWN_LINK, except inferred from text content. iykyk.
• LOWDOWN_LIST — a list enclosure described by <ul> or <ol>.
• LOWDOWN_LISTITEM — a list item described by <li>.
• LOWDOWN_MATH_BLOCK — a snippet of mathematical text in LaTeX format described within \[xx\] or \(xx\). This is usually (in HTML) externally handled by a JavaScript renderer. 🧮
• LOWDOWN_META — meta-data keys and values. These are described by elements in <head>.
• LOWDOWN_NORMAL_TEXT — normal text content.
• LOWDOWN_PARAGRAPH — a block-level paragraph described by <p>.
• LOWDOWN_RAW_HTML — an inline of raw HTML. (Only if configured during parse.)
• LOWDOWN_ROOT — the root of the document. This is always the topmost node, and the only node where the parent field is NULL. 👑
• LOWDOWN_STRIKETHROUGH — content struck through. Described by <del>.
• LOWDOWN_SUBSCRIPT, LOWDOWN_SUPERSCRIPT — a subscript or superscript described by <sub> or <sup>, respectively.
• LOWDOWN_TABLE_BLOCK — a table block described by <table>.
• LOWDOWN_TABLE_BODY — a table body section described by <tbody>.
• LOWDOWN_TABLE_CELL — a table cell described by <td>, or <th> if in the header.
• LOWDOWN_TABLE_HEADER — a table header section described by <thead>.
• LOWDOWN_TABLE_ROW — a table row described by <tr>.
• LOWDOWN_TRIPLE_EMPHASIS — combination of LOWDOWN_EMPHASIS and LOWDOWN_DOUBLE_EMPHASIS.

okay so now the actual fields of the node struct, bestie — these are lowkey important:

• size_t id — an identifier unique within the document. This can be used as a table index since the number is assigned from a monotonically increasing point during the parse. 🔢
• struct lowdown_node *parent — the parent of the node, or NULL at the root.
• enum lowdown_chng chng — change tracking: whether this node was inserted (LOWDOWN_CHNG_INSERT), deleted (LOWDOWN_CHNG_DELETE), or neither (LOWDOWN_CHNG_NONE).
• struct lowdown_nodeq children — a possibly-empty list of child nodes. 🫶
• <anon union> — an anonymous union of type-specific structures. Inside it:
  • rndr_autolink — for LOWDOWN_LINK_AUTO, the link address as link and the link type type, which may be one of HALINK_EMAIL for e-mail links and HALINK_NORMAL otherwise. Any buffer may be empty-sized.
  • rndr_blockcode — for LOWDOWN_BLOCKCODE, the opaque text of the block and the optional lang of the code language. 💻
  • rndr_blockhtml — for LOWDOWN_BLOCKHTML, the opaque HTML text.
  • rndr_codespan — the opaque text of the contents.
  • rndr_definition — for LOWDOWN_DEFINITION, containing flags that may be HLIST_FL_BLOCK if the definition list should be interpreted as containing block nodes.
  • rndr_entity — for LOWDOWN_ENTITY, the entity text.
  • rndr_header — for LOWDOWN_HEADER, the level of the header starting at zero (this value is relative to the metadata base header level, defaulting to one). Arbitrary key-value attributes are stored in attrs of length attrsz, which are NULL and 0, respectively, if there are no attributes. ✨
  • rndr_image — for LOWDOWN_IMAGE, the image address link, the image title title, dimensions NxN (width by height) in dims, and alternate text alt. Arbitrary key-value attributes are stored in attrs of length attrsz, which are NULL and 0, respectively, if there are no attributes. 🖼️
  • rndr_link — like rndr_autolink, but without a type and further defining an optional link title title. Arbitrary key-value attributes are stored in attrs of length attrsz, which are NULL and 0, respectively, if there are no attributes.
  • rndr_list — for LOWDOWN_LIST, consists of a bitfield flags that may be set to HLIST_FL_ORDERED for an ordered list and HLIST_FL_UNORDERED for an unordered one. If HLIST_FL_BLOCK is set, the list should be output as if items were separate blocks. The start value for HLIST_FL_ORDERED is the starting list item position, which is one by default and never zero. The items is the number of list items.
  • rndr_listitem — for LOWDOWN_LISTITEM, consists of a bitfield flags that may be set to HLIST_FL_ORDERED for an ordered list, HLIST_FL_UNORDERED for an unordered list, HLIST_FL_DEF for definition list data, HLIST_FL_CHECKED or HLIST_FL_UNCHECKED for an unordered “task” list, and/or HLIST_FL_BLOCK for list item output as if containing block nodes. ⚠️ The HLIST_FL_BLOCK should not be used: use the parent list (or definition list) flags for this. The num is the index in a HLIST_FL_ORDERED list. It is monotonically increasing with each item in the list, starting at the start variable given in struct rndr_list.
  • rndr_math — for LOWDOWN_MATH, the mode of display in blockmode: if 1, in-line math; if 2, multi-line. The opaque equation, which is assumed to be in LaTeX format, is in the opaque text. 🧮
  • rndr_meta — each LOWDOWN_META key-value pair is represented. The keys are lower-case without spaces or non-ASCII characters. If provided, enclosed nodes may consist only of LOWDOWN_NORMAL_TEXT and LOWDOWN_ENTITY.
  • rndr_normal_text — the basic text content for LOWDOWN_NORMAL_TEXT. If flags is set to HTEXT_ESCAPED, the text may be escaped for output, but may not be altered by any smart typography or similar (it should be passed as-is). 🫶
  • rndr_paragraph — for LOWDOWN_PARAGRAPH, specifies how many lines the paragraph has in the input file and beoln, set to non-zero if the paragraph ends with an empty line instead of a breaking block node.
  • rndr_raw_html — for LOWDOWN_RAW_HTML, the opaque HTML text.
  • rndr_table — for LOWDOWN_TABLE_BLOCK, the number of columns in each row or header row. The number of columns in rndr_table, rndr_table_header, and rndr_table_cell are the same.
  • rndr_table_cell — for LOWDOWN_TABLE_CELL, the current col column number out of columns. See rndr_table_header for a description of the bits in flags. The number of columns in rndr_table, rndr_table_header, and rndr_table_cell are the same.
  • rndr_table_header — for LOWDOWN_TABLE_HEADER, the number of columns in each row and the per-column flags, which may tested for equality against HTBL_FL_ALIGN_LEFT, HTBL_FL_ALIGN_RIGHT, or HTBL_FL_ALIGN_CENTER after being masked with HTBL_FL_ALIGNMASK; or HTBL_FL_HEADER. If no alignment is specified after the mask, the default should be left-aligned. The number of columns in rndr_table, rndr_table_header, and rndr_table_cell are the same. 💅

🌳 ABSTRACT SYNTAX TREE 🌳

okay bestie so a parsed document? it's literally a tree of struct lowdown_node nodes. that's the whole vibe ✨

here's the tea on how nodes behave:

• if a node is block, it can hold other block nodes or inline nodes inside it 🫶
• if it's inline, it can only hold other inline nodes, no exceptions, periodt
• special nodes are the quirky ones — they're documented down below 💅
• and if you see void tacked on? that means the node will never have children. ever. empty nest energy 🪹

okay so here's the full cast of characters and their scopes, no cap:

• LOWDOWN_BLOCKCODE — block, void
• LOWDOWN_BLOCKHTML — block, void
• LOWDOWN_BLOCKQUOTE — block
• LOWDOWN_CODESPAN — inline, void
• LOWDOWN_DEFINITION — block
• LOWDOWN_DEFINITION_DATA — special
• LOWDOWN_DEFINITION_TITLE — special
• LOWDOWN_DOC_HEADER — special
• LOWDOWN_DOUBLE_EMPHASIS — inline
• LOWDOWN_EMPHASIS — inline
• LOWDOWN_ENTITY — inline, void
• LOWDOWN_FOOTNOTE — block, special
• LOWDOWN_HEADER — block
• LOWDOWN_HRULE — inline, void
• LOWDOWN_IMAGE — inline, void
• LOWDOWN_LINEBREAK — inline, void
• LOWDOWN_LINK — inline
• LOWDOWN_LINK_AUTO — inline, void
• LOWDOWN_LIST — block
• LOWDOWN_LISTITEM — special
• LOWDOWN_MATH_BLOCK — inline, void
• LOWDOWN_META — special
• LOWDOWN_NORMAL_TEXT — inline, void
• LOWDOWN_PARAGRAPH — block
• LOWDOWN_RAW_HTML — inline, void
• LOWDOWN_ROOT — special
• LOWDOWN_STRIKETHROUGH — inline
• LOWDOWN_SUBSCRIPT — inline
• LOWDOWN_SUPERSCRIPT — inline
• LOWDOWN_TABLE_BLOCK — block
• LOWDOWN_TABLE_BODY — special
• LOWDOWN_TABLE_CELL — special
• LOWDOWN_TABLE_HEADER — special
• LOWDOWN_TABLE_ROW — special
• LOWDOWN_TRIPLE_EMPHASIS — inline

---

🧚 the general shape of it all 🧚

so the overall structure of the AST goes like this. heads up: nodes have no order imposed on them unless it says so, mmkay? 🎀

• LOWDOWN_ROOT (ordered)
  • LOWDOWN_DOC_HEADER
    • LOWDOWN_META
      • LOWDOWN_ENTITY
      • LOWDOWN_NORMAL_TEXT
  • (zero or more block nodes)

and the special nodes? they each have their own little spot in their parents, like assigned seating at lunch:

• LOWDOWN_DEFINITION (one or more ordered pairs of...)
  • LOWDOWN_DEFINITION_TITLE
    • (inline nodes)
  • LOWDOWN_DEFINITION_DATA
    • (block nodes)
• LOWDOWN_HEADER
  • (inline nodes)
• LOWDOWN_LIST
  • LOWDOWN_LISTITEM
    • (inline or block nodes, depending)
• LOWDOWN_TABLE_BLOCK (ordered)
  • LOWDOWN_TABLE_HEADER (zero or more...)
    • LOWDOWN_TABLE_ROW (one or more...)
      • LOWDOWN_TABLE_CELL
        • (inline nodes)
  • LOWDOWN_TABLE_BODY (zero or more...)
    • LOWDOWN_TABLE_ROW (one or more...)
      • LOWDOWN_TABLE_CELL
        • (inline nodes)

and lastly — and this is the fun part — LOWDOWN_FOOTNOTE can just appear anywhere in the document like it owns the place 👑 and it contains block nodes.

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🌈 SEE ALSO 🌈

the whole friend group, fr fr — go read these next:

• lowdown(1)
• lowdown_buf(3)
• lowdown_buf_diff(3)
• lowdown_diff(3)
• lowdown_doc_free(3)
• lowdown_doc_new(3)
• lowdown_doc_parse(3)
• lowdown_file(3)
• lowdown_file_diff(3)
• lowdown_gemini_free(3)
• lowdown_gemini_new(3)
• lowdown_gemini_rndr(3)
• lowdown_html_free(3)
• lowdown_html_new(3)
• lowdown_html_rndr(3)
• lowdown_latex_free(3)
• lowdown_latex_new(3)
• lowdown_latex_rndr(3)
• lowdown_metaq_free(3)
• lowdown_roff_free(3)
• lowdown_roff_new(3)
• lowdown_roff_rndr(3)
• lowdown_odt_free(3)
• lowdown_odt_new(3)
• lowdown_odt_rndr(3)
• lowdown_term_free(3)
• lowdown_term_new(3)
• lowdown_term_rndr(3)
• lowdown_tree_rndr(3)
• lowdown(5)

---

✨ AUTHORS ✨

okay so lowdown was forked from hoedown — that's https://github.com/hoedown/hoedown — by Kristaps Dzonsons, kristaps@bsd.lv 💖 and it's been considerably modified since. like, glow-up levels of modified. obsessed. 🦋

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and that's a wrap bestie!! 🎀 this page is from Debian, version $Mdocdate$, and it's literally called LOWDOWN(3) — go forth and parse some trees, you absolute icon 💅✨