~bzg/worg

cc46f18f643a78f86f76d99656dc8a35d0ea5a69 — TEC 18 days ago 27758c2
Upload rewrite of org-syntax as org-syntax-edited
1 files changed, 2020 insertions(+), 0 deletions(-)

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#+title: Org Syntax
#+subtitle: DRAFT v2_{\beta}
#+author: Nicolas Goaziou, Timothy E Chapman
#+options: toc:t ':t author:nil
#+language: en
#+category: worg
#+bind: sentence-end-double-space t
#+html_link_up:    index.html
#+html_link_home:  https://orgmode.org/worg/

#+begin_comment
This file is released by its authors and contributors under the GNU
Free Documentation license v1.3 or later, code examples are released
under the GNU General Public License v3 or later.
#+end_comment

* Introduction

Org is a plaintext format composed of simple, yet versatile, forms
which represent formatting and structural information.  It is designed
to be both intuitive to use, and capable of representing complex
documents.  Like [[https://datatracker.ietf.org/doc/html/rfc7763][Markdown]], Org may be considered a lightweight markup
language.  However, while Markdown refers to a collection of similar
syntaxes, Org is a single syntax.

This document describes and comments on Org syntax as it is currently
read by its parser (=org-element.el=) and, therefore, by the export
framework.

* Terminology and conventions

** Objects and Elements

The components of this syntax can be divided into two classes:
"[[#Objects][objects]]" and "[[#Elements][elements]]".  To better understand these classes,
consider the paragraph as a unit of measurement.  /Elements/ are
syntactic components that exist at the same or greater scope than a
paragraph, i.e. which could not be contained by a paragraph.
Conversely, /objects/ are syntactic components that exist with a smaller
scope than a paragraph, and so can be contained within a paragraph.

Elements can be stratified into "[[#Headings][headings]]", "[[#Sections][sections]]", "[[#Greater_Elements][greater
elements]]", and "[[#Lesser_Elements][lesser elements]]", from broadest scope to
narrowest.  Along with objects, these sub-classes define categories of
syntactic environments.  Only [[#Headings][headings]], [[#Sections][sections]], [[#Property_Drawers][property drawers]], and
[[#Planning][planning lines]] are context-free[fn:1][fn:2], every other syntactic
component only exists within specific environments. This is a core
concept of the syntax.

Expanding on the stratification of elements, lesser elements are
elements that cannot contain any other elements.  As such, a paragraph
is considered a lesser element.  Greater elements can themselves
contain greater elements or lesser elements. Sections contain both
greater and lesser elements, and headings can contain a section and
other headings.

** The minimal and standard sets of objects

To simplify references to common collections of objects, we define two
useful sets.  The /<<<minimal set>>> of objects/ refers to [[#Plain_Text][plain text]], [[#Emphasis_Markers][text
markup]], [[#Entities][entities]], [[#LaTeX_Fragments][LaTeX fragments]], [[#Subscript_and_Superscript][superscripts and subscripts]].  The
/<<<standard set>>> of objects/ refers to the entire set of objects, excluding
citation references and [[#Table_Cells][table cells]].

** Blank lines

A line containing only spaces, tabs, newlines, and line feeds (=\t\n\r=)
is considered a /blank line/.  Blank lines can be used to separate
paragraphs and other elements.

With the exception of [[#Items][list items]], blank lines belong to the preceding
element with the narrowest possible scope.  For example, if at the end
of a section we have a paragraph and a blank line, that blank line is
considered part of the paragraph.

** Indentation

Indentation consists of a series of space and tab characters at the
beginning of a line. Most elements can be indentated, with the
exception of [[#Headings][headings]], [[#Inlinetasks][inlinetasks]], [[#Footnote_Definitions][footnote definitions]], and [[#Diary_Sexp][diary
sexps]].

** Case significance

In this document, unless specified otherwise, case is insignificant.

** Syntax patterns

*** General form

Most elements and objects will be described with the help of syntax
patterns, consisting of a series of named tokens written in uppercase
and separated by a space, like so:
#+begin_example
TOKEN1 TOKEN2
#+end_example

These tokens are often named roughly according to their semantic
meaning, For instance, "KEY" and "VALUE" when describing
[[#Keywords][Keywords]]. Tokens will be specified as either a string, or a series of
elements or objects.

Unless otherwise specified, a space in a pattern represents one or
more horizontal whitespace characters.

Patterns will often also contain static structures that serve to
differentiate a particular element or object type from others, but
have no semantic meaning.  These are simply included in the pattern
verbatim.  For instance, if a pattern consists of two plus signs (=+=)
immediately followed by a TOKEN it would be written like so:
#+begin_example
++TOKEN
#+end_example

Since tokens are written in uppercase, any letters in static
structures are distinguished by being written in lowercase.

*** Special tokens
:PROPERTIES:
:CUSTOM_ID: Special_Tokens
:END:

In a few cases, an instance of an element or object must be preceded
or succeeded by a certain pattern, which is not itself part of the
element or object.  There patterns are specified using the /PRE/ and
/POST/ tokens respectively, like so:
#+begin_example
PRE TOKEN POST
#+end_example

* Elements
:PROPERTIES:
:CUSTOM_ID: Elements
:END:
** Headings and Sections
:PROPERTIES:
:CUSTOM_ID: Headings_and_Sections
:END:
*** Headings
:PROPERTIES:
:CUSTOM_ID: Headings
:END:

A Heading is a /unindented/ line structured according to the following pattern:

#+begin_example
STARS KEYWORD PRIORITY TITLE TAGS
#+end_example

+ STARS :: A string consisting of one or more asterisks (up to
  ~org-inlinetask-min-level~ if the =org-inlinetask= library is loaded)
  and ended by a space character.  The number of asterisks is used to
  define the level of the heading.

+ KEYWORD (optional) :: A string which is a member of
  ~org-todo-keywords-1~[fn:otkw1:By default, ~org-todo-keywords-1~ only
  contains =TODO= and =DONE=, however this is liable to change.].  Case is
  significant.  This is called a "TODO keyword".

+ PRIORITY (optional) :: A single alphanumeric character preceded by a
  hash sign =#= and enclosed within square brackets (e.g. =[#A]= or =[#1]=).  This
  is called a "priority cookie".

+ TITLE (optional) :: A series of objects from the standard set,
  excluding line break objects.  It is matched after every other part.

+ TAGS (optional) :: A series of colon-separated strings consisting of
  alpha-numeric characters, underscores, at signs, hash signs, and
  percent signs (=_@#%=).

*Examples*

#+begin_example
,*
,** DONE
,*** Some e-mail
,**** TODO [#A] COMMENT Title :tag:a2%:
#+end_example

If the first word appearing in the title is =COMMENT=, the heading
will be considered as "commented".  Case is significant.

If its title is the value of ~org-footnote-section~ (=Footnotes= by
default), it will be considered as a "footnote section".  Case is
significant.

If =ARCHIVE= is one of the tags given, the heading will be considered as
"archived".  Case is significant.

A heading contains directly one section (optionally), followed by
any number of deeper level headings.

*** Sections
:PROPERTIES:
:CUSTOM_ID: Sections
:END:

Sections contain one or more non-heading elements.  With the exception
of the text before the first heading in a document (which is
considered a section), sections only occur within headings.

*Example*

Consider the following document:

#+begin_example
An introduction.
,* A Heading
Some text.
,** Sub-Topic 1
,** Sub-Topic 2
,*** Additional entry
#+end_example

Its internal structure could be summarized as:

#+begin_example
(document
 (section)
 (heading
  (section)
  (heading)
  (heading
   (heading))))
#+end_example

*** The top level section
:PROPERTIES:
:CUSTOM_ID: Top_level_section
:END:

All elements before the first heading in a document lie in a special
section called the /top level section/.  It may be preceded by blank
lines.  Unlike a normal section, the top level section can immediately
contain a [[#Property_Drawers][property drawer]], optionally preceded by [[#Comments][comments]].  It cannot
however, contain [[Planning][planning]].

** Affiliated Keywords
:PROPERTIES:
:CUSTOM_ID: Affiliated_Keywords
:END:

With the exception of [[#Comments][comments]], [[#Clocks][clocks]], [[#Headings][headings]], [[#Inlinetasks][inlinetasks]],
[[#Items][items]], [[#Node_Properties][node properties]], [[#Planning][planning]], [[#Property_Drawers][property drawers]], [[#Sections][sections]], and
[[#Table_Rows][table rows]], every other element type can be assigned attributes.

This is done by adding specific [[#Keywords][keywords]], named /affiliated/ keywords,
immediately above the element considered (a blank line cannot lie
between the affiliated keyword and element). Structurally, affiliated
keyword are not considered an element in their own right but a
property of the element they apply to.

Affiliated keywords are structured according to one of the following pattern:

#+begin_example
,#+KEY: VALUE
,#+KEY[OPTVAL]: VALUE
,#+attr_BACKEND: VALUE
#+end_example

+ KEY :: A string which is a member of
  ~org-element-affiliated-keywords~[fn:oeakw:By default,
  ~org-element-affiliated-keywords~ contains =CAPTION=, =DATA=, =HEADERS=,
  =LABEL=, =NAME=, =PLOT=, =RESNAME=, =RESULT=, =RESULTS=, =SOURCE=, =SRCNAME=, and
  =TBLNAME=.].
+ BACKEND :: A string consisting of alphanumeric characters, hyphens,
  or underscores (=-_=).
+ OPTVAL (optional) :: A string consisting of any characters but a
  newline.  This term is only valid when KEY is a member of
  ~org-element-dual-keywords~[fn:oedkw:By default,
  ~org-element-dual-keywords~ contains =CAPTION= and =RESULTS=.].
+ VALUE :: A string consisting of any characters but a newline, except
  in the case where KEY is member of
  ~org-element-parsed-keywords~[fn:oepkw:By default,
  ~org-element-parsed-keywords~ contains =CAPTION=.] in
  which case VALUE can contain the standard set of objects, excluding
  footnote references.

Repeating an affiliated keyword before an element will usually result
in the prior VALUEs being overwritten by the last instance of KEY.
There are two situations under which the VALUEs will be concatenated:
1. If KEY is a member of ~org-element-dual-keywords~[fn:oedkw].
2. If the affiliated keyword is an instance of the patten
   =#+attr_BACKEND: VALUE=.

The following example contains three affiliated keywords:
#+begin_example
,#+name: image-name
,#+caption: This is a caption for
,#+caption: the image linked below
[[file:some/image.png]]
#+end_example

** Greater Elements
:PROPERTIES:
:CUSTOM_ID: Greater_Elements
:END:

Unless specified otherwise, greater elements can contain directly
any greater or [[#Lesser_Elements][lesser element]] except:
+ Elements of their own type.
+ [[#Planning][Planning]], which may only occur in a [[#Headings][heading]].
+ [[#Property_Drawers][Property drawers]], which may only occur in a [[#Headings][heading]] or the [[#Top_level_section][top level
  section]].
+ [[#Node_Properties][Node properties]], which can only be found in [[#Property_Drawers][property drawers]].
+ [[#Items][Items]], which may only occur in [[#Plain_Lists][plain lists]].
+ [[#Table_Rows][Table rows]], which may only occur in [[#Tables][tables]].

*** Greater Blocks
:PROPERTIES:
:CUSTOM_ID: Greater_Blocks
:END:

Greater blocks are structured according to the following pattern:
#+begin_example
,#+begin_NAME PARAMETERS
CONTENTS
,#+end_NAME
#+end_example

+ NAME :: A string consisting of any non-whitespace characters, which
  is not the NAME of a [[#Blocks][lesser block]].  Greater blocks are treated
  differently based on their subtype, which is determined by the NAME
  as follows:
  - =center=, a "center block"
  - =quote=, a "quote block"
  - any other value, a "special block"
+ PARAMETERS (optional) :: A string consisting of any characters other
  than a newline.
+ CONTENTS :: A collection of zero or more elements, subject to two
  conditions:
  - No line may start with =#+end_NAME=.
  - Lines beginning with an asterisk must be quoted by a comma (=,*=).
  Furthermore, lines starting with =#+= may be quoted by a comma (=,#+=).

*** Drawers and Property Drawers
:PROPERTIES:
:CUSTOM_ID: Drawers
:END:

Drawers are structured according to the following pattern:
#+begin_example
:NAME:
CONTENTS
:end:
#+end_example

+ NAME :: A string consisting of word-constituent characters, hyphens
  and underscores (=-_=).
+ CONTENTS :: A collection of zero or more elements, except another drawer.

*** Dynamic Blocks
:PROPERTIES:
:CUSTOM_ID: Dynamic_Blocks
:END:

Dynamic blocks are structured according to the following pattern:
#+begin_example
,#+begin: NAME PARAMETERS
CONTENTS
,#+end:
#+end_example

+ NAME :: A string consisting of non-whitespace characters.
+ PARAMETERS (optional) :: A string consisting of any characters but a newline.
+ CONTENTS :: A collection of zero or more elements, except another
  dynamic block.

*** Footnote Definitions
:PROPERTIES:
:CUSTOM_ID: Footnote_Definitions
:END:

Footnote definitions must occur at the start of an /unindented/ line,
and are structured according to the following pattern:
#+begin_example
[fn:LABEL] CONTENTS
#+end_example

+ LABEL :: Either a number or an instance of the pattern =fn:WORD=, where
  =WORD= represents a string consisting of word-constituent characters,
  hyphens and underscores (=-_=).

+ CONTENTS (optional) :: A collection of zero or more elements.  It
  ends at the next footnote definition, the next heading, two
  consecutive blank lines, or the end of buffer.

*Examples*

#+begin_example
[fn:1] A short footnote.

[fn:2] This is a longer footnote.

It even contains a single blank line.
#+end_example


*** Inlinetasks
:PROPERTIES:
:CUSTOM_ID: Inlinetasks
:END:

Inlinetasks are syntactically a [[#Headings][heading]] with a level of at least
~org-inlinetask-min-level~[fn:oiml:The default value of
~org-inlinetask-min-level~ is =15=.], i.e. starting with at least that
many asterisks.

Optionally, inlinetasks can be ended with a second heading with a
level of at least ~org-inlinetask-min-level~[fn:oiml], with no optional
components (i.e. only STARS and TITLE provided) and the string =END= as
the TITLE. This allows the inlinetask to contain elements.

*Examples*

#+begin_example
,*************** TODO some tiny task
This is a paragraph, it lies outside the inlinetask above.
,*************** TODO some small task
                 DEADLINE: <2009-03-30 Mon>
                 :PROPERTIES:
                   :SOMETHING: or other
                 :END:
                 And here is some extra text
,*************** END
#+end_example

Inlinetasks are only recognized after the =org-inlinetask= library is
loaded.

*** Items
:PROPERTIES:
:CUSTOM_ID: Items
:END:

Items are structured according to the following pattern:
#+begin_example
BULLET COUNTER-SET CHECK-BOX TAG CONTENTS
#+end_example

+ BULLET :: One of the two forms below, followed by either a
  whitespace character or line ending.
  - An asterisk, hyphen, or plus sign character (i.e., =*=, =-=, or =+=).
  - Either the pattern =COUNTER.= or =COUNTER)=.
    + COUNTER :: Either a number or a single letter (a-z).
+ COUNTER-SET (optional) :: An instance of the pattern =[@COUNTER]=.
+ CHECK-BOX (optional) :: A single whitespace character, an =X=
  character, or a hyphen enclosed by square brackets (i.e. =[ ]=, =[X]=, or =[-]=).
+ TAG (optional) :: An instance of the pattern =TAG-TEXT ::= where
  =TAG-TEXT= represents a string consisting of non-newline characters
  that does not contain the substring "\nbsp{}::\nbsp{}" (two colons surrounded by
  whitespace).
+ CONTENTS (optional) :: A collection of zero or more elements, ending
  at the first instance of one of the following:
  - The next item.
  - The first line less or equally indented than the starting line,
    not counting lines within other elements or [[#Inlinetasks][inlinetask]] boundaries.
  - Two consecutive blank lines.

*Examples*

#+begin_example
- item
3. [@3] set to three
+ [-] tag :: item contents
#+end_example

*** Plain Lists
:PROPERTIES:
:CUSTOM_ID: Plain_Lists
:END:

A /plain list/ is a set of consecutive [[#Items][items]] of the same indentation.

If first item in a plain list has a COUNTER in its BULLET, the plain
list will be an "ordered plain-list".  If it contains a TAG, it will
be a "descriptive list".  Otherwise, it will be an "unordered list".
List types are mutually exclusive.

For example, consider the following excerpt of an Org document:

#+begin_example
1. item 1
2. [X] item 2
   - some tag :: item 2.1
#+end_example

Its internal structure is as follows:

#+begin_example
(ordered-plain-list
 (item)
 (item
  (descriptive-plain-list
   (item))))
#+end_example

*** Property Drawers
:PROPERTIES:
:CUSTOM_ID: Property_Drawers
:END:

Property drawers are a special type of [[#Drawers][drawer]] containing properties
attached to a [[#Headings][heading]] or [[#Inlinetasks][inlinetask]].  They are located right after a heading
and its [[#Planning][planning]] information, as shown below:

#+begin_example
HEADLINE
PROPERTYDRAWER

HEADLINE
PLANNING
PROPERTYDRAWER
#+end_example

Property Drawers are structured according to the following pattern:

#+begin_example
:properties:
CONTENTS
:end:
#+end_example

+ CONTENTS :: A collection of zero or more [[#Node_Properties][node properties]], not
  separated by blank lines.

*Example*

#+begin_example
:PROPERTIES:
:CUSTOM_ID: someid
:END:
#+end_example

*** Tables
:PROPERTIES:
:CUSTOM_ID: Tables
:END:

Tables are started by a line beginning with either:
+ A vertical bar (=|=), forming an "org" type table.
+ The string =+-= followed by a sequence of plus (=+=) and minus (=-=)
  signs, forming a "table.el" type table.

Tables cannot be immediately preceded by such lines, as the current
line would the be part of the earlier table.

Org tables contain table rows, and end at the first line not starting
with a vertical bar. An Org table can be followed by a number of
=#+TBLFM: FORMULAS= lines, where =FORMULAS= represents a string consisting
of any characters but a newline.

Table.el tables end at the first line not starting with either
a vertical line or a plus sign.

*Example*

#+begin_example
| Name  | Phone | Age |
|-------+-------+-----|
| Peter |  1234 |  24 |
| Anna  |  4321 |  25 |
#+end_example

** Lesser Elements
:PROPERTIES:
:CUSTOM_ID: Lesser_Elements
:END:

Lesser elements cannot contain any other element.

Only [[#Keywords][keywords]] which are a member of ~org-element-parsed-keywords~[fn:oepkw], [[#Blocks][verse
blocks]], [[#Paragraphs][paragraphs]] or [[#Table_Rows][table rows]] can contain objects.

*** Babel Call
:PROPERTIES:
:CUSTOM_ID: Babel_Call
:END:

Babel calls are structured according to one of the following patterns:
#+begin_example
,#+call: NAME(ARGUMENTS)
,#+call: NAME[HEADER1](ARGUMENTS)
,#+call: NAME(ARGUMENTS)[HEADER2]
,#+call: NAME[HEADER1](ARGUMENTS)[HEADER2]
#+end_example

+ NAME :: A string consisting of any non-newline characters except for
  square brackets, or parentheses (=[]()=).
+ ARGUMENTS (optional) :: A string consisting of any non-newline
  characters.  Opening and closing parenthesis must be balanced.
+ HEADER1 (optional), HEADER2 (optional) :: A string consisting of any
  non-newline characters.  Opening and closing square brackets must be
  balanced.

*** Blocks
:PROPERTIES:
:CUSTOM_ID: Blocks
:END:

Like [[#Greater_Blocks][greater blocks]], blocks are structured according to the following pattern:

#+begin_example
,#+begin_NAME DATA
CONTENTS
,#+end_NAME
#+end_example

+ NAME :: A string consisting of any non-whitespace characters.  The
  type of the block is determined based on the value as follows:
  - =comment=, a "comment block",
  - =example=, an "example block",
  - =export=, an "export block",
  - =src=, a "source block",
  - =verse=, a "verse block".
    The NAME must be one of these values.  Otherwise, the pattern
    forms a greater block.
+ DATA (optional) :: A string consisting of any characters but a newline.
  - In the case of an export block, this is mandatory and must be a
    single word.
  - In the case of a source block, this is mandatory and must follow
    the pattern =LANGUAGE SWITCHES ARGUMENTS= with:
    + LANGUAGE :: A string consisting of any non-whitespace characters
    + SWITCHES :: Any number of SWITCH patterns, separated by a single
      space character
      - SWITCH :: Either the pattern =-l "FORMAT"= where =FORMAT=
        represents a string consisting of any characters but a double
        quote (="=) or newline, or the pattern =-S= or =+S= where =S=
        represents a single alphabetic character
    + ARGUMENTS :: A string consisting of any character but a newline.
+ CONTENTS (optional) :: A string consisting of any characters
  (including newlines) subject to the same two conditions of greater
  block's CONTENTS, i.e.
  - No line may start with =#+end_NAME=.
  - Lines beginning with an asterisk must be quoted by a comma (=,*=).
  As with greater blocks, lines starting with =#+= may be quoted by a
  comma (=,#+=).
  CONTENTS will contain Org objects when the block is a verse block,
  it is otherwise not parsed.

*Example*

#+begin_example
,#+begin_verse
    There was an old man of the Cape
   Who made himself garments of crepe.
       When asked, “Do they tear?”
      He replied, “Here and there,
 But they’re perfectly splendid for shape!”
,#+end_verse
#+end_example

*** Clock
:PROPERTIES:
:CUSTOM_ID: Clocks
:END:

A clock element is structured according to the following pattern:

#+begin_example
clock: INACTIVE-TIMESTAMP
clock: INACTIVE-TIMESTAMP-RANGE DURATION
#+end_example

+ INACTIVE-TIMESTAMP :: An inactive [[#Timestamps][timestamp]] object.
+ INACTIVE-TIMESTAMP-RANGE :: An inactive range [[#Timestamps][timestamp]] object.
+ DURATION :: An instance of the pattern ==> HH:MM=.
  - HH :: A number consisting of any number of digits.
  - MM :: A two digit number.

*Example*

#+begin_example
clock: [2024-10-12]
#+end_example


*** Diary Sexp
:PROPERTIES:
:CUSTOM_ID: Diary_Sexp
:END:

A diary sexp[fn::A common abbreviation for S-expression] element is an
/unindented/ line structured according to the following pattern:

#+begin_example
%%SEXP
#+end_example

+ SEXP :: A string starting with an open parenthesis =(=, with balanced
  opening and closing parentheses.

*Example*

#+begin_example
%%(org-calendar-holiday)
#+end_example

*** Planning
:PROPERTIES:
:CUSTOM_ID: Planning
:END:

A planning element is structured according to the following pattern:

#+begin_example
HEADING
PLANNING
#+end_example

+ HEADING :: A [[#Headings][heading]] element.
+ PLANNING :: A line consisting of a series of =KEYWORD: TIMESTAMP=
  patterns (termed "info" patterns).
  - KEYWORD :: Either the string =DEADLINE=, =SCHEDULED=, or =CLOSED=.
  - TIMESTAMP :: A [[#Timestamps][timestamp]] object.

It is not permitted for any blank lines to lie between HEADING and
PLANNING.

*Example*

#+begin_example
,*** TODO watch "The Matrix"
    SCHEDULED: <1999-03-31 Wed>
#+end_example

*** Comments
:PROPERTIES:
:CUSTOM_ID: Comments
:END:

A "comment line" starts with a hash character (=#=) and either a whitespace
character or the immediate end of the line.

Comments consist of one or more consecutive comment lines.

*Example*

#+begin_example
# Just a comment
#
# Over multiple lines
#+end_example


*** Fixed Width Areas
:PROPERTIES:
:CUSTOM_ID: Fixed_Width_Areas
:END:

A "fixed-width line" starts with a colon character (=:=) and either a whitespace
character or the immediate end of the line.

Fixed-width areas consist of one or more consecutive fixed-width lines.

*Example*

#+begin_example
: This is a
: fixed width area
#+end_example

*** Horizontal Rules
:PROPERTIES:
:CUSTOM_ID: Horizontal_Rules
:END:

A horizontal rule is formed by a line consisting of at least five
consecutive hyphens (=-----=).

*** Keywords
:PROPERTIES:
:CUSTOM_ID: Keywords
:END:

Keywords are structured according to the following pattern:

#+begin_example
,#+KEY: VALUE
#+end_example

+ KEY :: A string consisting of any non-whitespace characters, other
  than =call= (which would forms a [[#Babel_Call][babel call]] element).
+ VALUE :: A string consisting of any characters but a newline.

When KEY is a member of ~org-element-parsed-keywords~[fn:oepkw], VALUE can contain
the standard set objects, excluding footnote references.

Note that while instances of this pattern are preferentially parsed as
[[#Affiliated_Keywords][affiliated keywords]], a keyword with the same KEY as an affiliated
keyword may occur so long as it is not immediately preceding a valid
element that can be affiliated.  For example, an instance of
=#+caption: hi= followed by a blank line will be parsed as a keyword,
not an affiliated keyword.

*** LaTeX Environments
:PROPERTIES:
:CUSTOM_ID: LaTeX_Environments
:END:

LaTeX environments are structured according to the following pattern:

#+begin_example
\begin{NAME}
CONTENTS
\end{NAME}
#+end_example

+ NAME :: A string consisting of alphanumeric or asterisk characters
+ CONTENTS (optional) :: A string which does not contain the substring
  =\end{NAME}=.

*** Node Properties
:PROPERTIES:
:CUSTOM_ID: Node_Properties
:END:

Node properties can only exist in [[#Property_Drawers][property drawers]], and are structured
according to one of the following patterns:

#+begin_example
:NAME: VALUE
:NAME:
:NAME+: VALUE
:NAME+:
#+end_example

+ NAME :: A non-empty string containing any non-whitespace characters
  which does not end in a plus characters (=+=).
+ VALUE (optional) :: A string containing any characters but a newline.

*** Paragraphs
:PROPERTIES:
:CUSTOM_ID: Paragraphs
:END:

Paragraphs are the default element, which means that any
unrecognized context is a paragraph.

Empty lines and other elements end paragraphs.

Paragraphs can contain the standard set of objects.

*** Table Rows
:PROPERTIES:
:CUSTOM_ID: Table_Rows
:END:

A table row consists of a vertical bar (=|=) followed by:
+ Any number of [[#Table_Cells][table cells]], forming a "standard" type row.
+ A hyphen (=-=), forming a "rule" type row.  Any non-newline characters
  can follow the hyphen and this will still be a "rule" type row

Table rows can only exist in [[#Tables][tables]].

* Objects
:PROPERTIES:
:CUSTOM_ID: Objects
:END:

Objects can only be found in the following elements:

- [[#Keywords][keywords]] or [[#Affiliated_Keywords][affiliated keywords]] VALUEs, when KEY is a member of
  ~org-element-parsed-keywords~[fn:oepkw],
- [[#Headings][heading]] TITLEs,
- [[#Inlinetasks][inlinetask]] TITLEs,
- [[#Items][item]] TAGs,
- [[#Clocks][clock]] INACTIVE-TIMESTAMP and INACTIVE-TIMESTAMP-RANGE, which can
  only contain inactive timestamps,
- [[#Planning][planning]] TIMESTAMPs, which can only be timestamps,
- [[#Paragraphs][paragraphs]],
- [[#Table_Cells][table cells]],
- [[#Table_Rows][table rows]], which can only contain table cell objects,
- [[#Blocks][verse blocks]].

Most objects cannot contain objects.  Those which can will be
specified.  Furthermore, while many objects may contain newlines, a
blank line often terminates the element that the object is a part of,
such as a paragraph.

** Entities
:PROPERTIES:
:CUSTOM_ID: Entities
:END:

Entities are structured according to the following pattern:

#+begin_example
\NAME POST
#+end_example

Where NAME and POST are not separated by a whitespace character.

+ NAME :: A string with a valid association in either
  ~org-entities~[fn:oe:See the [[#Entities_List][appendix]] for a list of entities.] or
  ~org-entities-user~.
+ POST :: Either:
  - The end of line.
  - The string ={}=.
  - A non-alphabetic character.

*Example*

#+begin_example
\cent
#+end_example


** LaTeX Fragments
:PROPERTIES:
:CUSTOM_ID: LaTeX_Fragments
:END:

LaTeX fragments are structured according to one of the following patterns:

#+begin_example
\NAME BRACKETS
\(CONTENTS\)
\[CONTENTS\]
#+end_example

+ NAME :: A string consisting of alphabetic characters which does not
  have an association in either ~org-entities~ or ~org-entities-user~.
+ BRACKETS (optional) :: An instance of one of the following patterns,
  not separated from NAME by whitespace.
  #+begin_example
[CONTENTS1]
{CONTENTS1}
  #+end_example
  - CONTENTS1 :: A string consisting of any characters but ={=, =}=, =[=,
    =]=, or a newline.
  - CONTENTS2 :: A string consisting of any characters but ={=, =}=, or a newline.
+ CONTENTS :: A string consisting of any characters, so long as it does
  not contain the substring =\)= in the case of the
  second template, or =\]= in the case of the third template.

*Examples*

#+begin_example
\enlargethispage{2\baselineskip}
\(e^{i \pi}\)
#+end_example


Org also supports TeX-style inline LaTeX fragments, structured
according the following pattern:

#+begin_example
$$CONTENTS$$
PRE$CHAR$POST
PRE$BORDER1 BODY BORDER2$POST
#+end_example

+ [[#Special_Tokens][PRE]] :: Either the beginning of line or a character other than =$=.
+ CHAR :: A non-whitespace character that is not =.=, =,=, =?=, =;=, or a
  double quote (="=).
+ [[#Special_Tokens][POST]] :: Any punctuation character (including parentheses and
  quotes), a space character, or the end of line.
+ BORDER1 :: A non-whitespace character that is not =.=, =,=, =;=, or =$=.
+ BODY :: A string consisting of any characters except =$=, and which
  does not span more than three lines.
+ BORDER2 :: A non-whitespace character that is not =.=, =,=, or =$=.

*Example*

#+begin_example
$$1+1=2$$
#+end_example

#+attr_ascii: :width 5
-----

#+begin_quote
It would introduce incompatibilities with previous Org versions,
but support for ~$...$~ (and for symmetry, ~$$...$$~) constructs
ought to be removed.

They are slow to parse, fragile, redundant and imply false
positives.  --- ngz
#+end_quote

** Export Snippets
:PROPERTIES:
:CUSTOM_ID: Export_Snippets
:END:

Export snippets are structured according to the following pattern:

#+begin_example
@@BACKEND:VALUE@@
#+end_example

+ BACKEND :: A string consisting of alphanumeric characters and hyphens.
+ VALUE (optional) :: A string containing anything but the string =@@=.

** Footnote References
:PROPERTIES:
:CUSTOM_ID: Footnote_References
:END:

Footnote references are structured according to one of the following patterns:

#+begin_example
[fn:LABEL]
[fn:LABEL:DEFINITION]
[fn::DEFINITION]
#+end_example

+ LABEL :: A string containing one or more word constituent characters,
  hyphens and underscores (=-_=).
+ DEFINITION (optional) :: A series of objects from the standard set,
  so long as opening and closing square brackets are balanced within
  DEFINITION.

If the reference follows the second pattern, it is called an "inline
footnote".  If it follows the third pattern, i.e. if LABEL is omitted,
it is called an "anonymous footnote".

Note that the first pattern may not occur on an /unindented/ line, as it
is then a [[#Footnote_Definitions][footnote definition]].

** Citations
:PROPERTIES:
:CUSTOM_ID: Citations
:END:

Citations are structured according to the following pattern:

#+begin_example
[cite CITESTYLE: GLOBALPREFIX REFERENCES GLOBALSUFFIX]
#+end_example

Where "cite" and =CITESTYLE=, =KEYCITES= and =GLOBALSUFFIX= are /not/
separated by whitespace.  =KEYCITES=, =GLOBALPREFIX=, and =GLOBALSUFFIX=
must be separated by semicolons.  Whitespace after the leading colon
or before the closing square bracket is not significant.  All other
whitespace is significant.

+ CITESTYLE (optional) :: An instance of either the pattern =/STYLE= or =/STYLE/VARIANT=
  - STYLE :: A string made of any alphanumeric character, =_=, or =-=.
  - Variant :: A string made of any alphanumeric character, =_=, =-=, or =/=.
+ GLOBALPREFIX (optional) :: A series of objects from the standard set,
  so long as all square brackets are balanced within GLOBALPREFIX, and
  it does not contain any semicolons (=;=) or subsequence that matches
  =@KEY=.
+ REFERENCES :: One or more [[#Citation_References][citation reference]] objects, separated by
  semicolons (=;=).
+ GLOBALSUFFIX (optional) :: A series of objects from the standard set,
  so long as all square brackets are balanced within GLOBALSUFFIX, and
  it does not contain any semicolons (=;=) or subsequence that matches
  =@KEY=.

*Examples*

#+begin_example
[cite:@key]
[cite/t:see;@foo p. 7;@bar pp. 4;by foo]
[cite/a/f:c.f.;the very important @@atkey @ once;the crucial @baz vol. 3]
#+end_example

** Citation references
:PROPERTIES:
:CUSTOM_ID: Citation_References
:END:

A reference to an individual resource is given in a /citation reference/
object.  Citation references are only found within [[#Citations][citations]], and are
structured according to the following pattern:

#+begin_example
KEYPREFIX @KEY KEYSUFFIX
#+end_example
Where KEYPREFIX, @​KEY, and KEYSUFFIX are not separated by whitespace.

+ KEYPREFIX (optional) :: A series of objects from the minimal set,
  so long as all square brackets are balanced within KEYPREFIX, and
  it does not contain any semicolons (=;=) or subsequence that matches
  =@KEY=.
+ KEY :: A string made of any word-constituent character, =-=, =.=, =:=,
  =?=, =!=, =`=, ='=, =/=, =*=, =@=, =+=, =|=, =(=, =)=, ={=, =}=, =<=, =>=, =&=, =_=, =^=, =$=, =#=, =%=, or
  =~=.
+ KEYSUFFIX (optional) :: A series of objects from the minimal set,
  so long as all square brackets are balanced within KEYPREFIX, and
  it does not contain any semicolons (=;=).

** Inline Babel Calls
:PROPERTIES:
:CUSTOM_ID: Inline_Babel_Calls
:END:

Inline Babel calls are structured according to one of the following patterns:

#+begin_example
call_NAME(ARGUMENTS)
call_NAME[HEADER1](ARGUMENTS)[HEADER2]
#+end_example

+ NAME :: A string consisting of any non-whitespace characters except
  for square brackets or parentheses (=[](​)=).
+ ARGUMENTS (optional), HEADER1 (optional), HEADER2 (optional) :: A
  string consisting of any characters but a newline.  Opening and
  closing square brackets must be balanced.

** Source Blocks
:PROPERTIES:
:CUSTOM_ID: Source_Blocks
:END:

Inline source blocks follow any of the following patterns:

#+begin_example
src_LANG{BODY}
src_LANG[HEADERS]{BODY}
#+end_example

+ LANG :: A string consisting of any non-whitespace characters.
+ HEADERS (optional), BODY (optional) :: A string consisting of any
  characters but a newline.  Opening and closing square brackets must
  be balanced.

** Line Breaks
:PROPERTIES:
:CUSTOM_ID: Line_Breaks
:END:

Line breaks must occur at the end of an otherwise non-blank line, and
are structured according to the following pattern:

#+begin_example
\\SPACE
#+end_example

+ SPACE :: Zero or more tab and space characters.

** Links
:PROPERTIES:
:CUSTOM_ID: Links
:END:

While links are a single object, they come in four subtypes: "radio",
"angle", "plain", and "regular" links.

*** Radio Links

Radio-type links are structured according to the following pattern:

#+begin_example
PRE RADIO POST
#+end_example

+ [[#Special_Tokens][PRE]] :: A non-alphanumeric character.
+ RADIO :: A series of objects matched by some [[#Targets_and_Radio_Targets][radio target]].  It can
  contain the minimal set of objects.
+ [[#Special_Tokens][POST]] :: A non-alphanumeric character.

*Example*

#+begin_example
This is some <<<*important* information>>> which we refer to lots.
Make sure you remember the *important* information.
#+end_example

The first instance of =*important* information= defines a radio target,
which is matched by the second instance of =*important* information=,
forming a radio link.

*** Plain links

Plain-type links are structured according to the following pattern:

#+begin_example
PRE PROTOCOL:PATHPLAIN POST
#+end_example

+ [[#Special_Tokens][PRE]] :: A non word constituent character.
+ PROTOCOL :: A string which is a one of the link type strings in
  ~org-link-parameters~[fn:olp:By default, ~org-link-parameters~ defines
  links of type =file+sys=, =file+emacs=, =shell=, =news=, =mailto=, =https=,
  =http=, =ftp=, =help=, =file=, or =elisp=.].
+ PATHPLAIN :: A string containing any non-whitespace character but =(=, =)=,
  =<=, or =>=.  It must end with a word-constituent character, or any
  non-whitespace non-punctuation character followed by =/=.
+ [[#Special_Tokens][POST]] :: A non word constituent character.

*Example*

#+begin_example
Be sure to look at https://orgmode.org.
#+end_example

*** Angle links

Angle-type essentially provide a method to disambiguate plain links
from surrounding text, and are structured according to the following
pattern:

#+begin_example
<PROTOCOL:PATHANGLE>
#+end_example

+ PROTOCOL :: A string which is a one of the link type strings in
  ~org-link-parameters~[fn:olp]
+ PATHANGLE :: A string containing any character but =]=, =<=, =>= or =\n=.

The angle brackets allow for a more permissive PATH syntax, without
accidentally matching surrounding text.

*** Regular links

Plain-type links are structured according to one of the following two patterns:

#+begin_example
[[PATHREG]]
[[PATHREG][DESCRIPTION]]
#+end_example

+ PATHREG :: An instance of one of the seven following annotated patterns:
  #+begin_example
FILENAME               ("file" type)
PROTOCOL:PATHINNER     ("PROTOCOL" type)
PROTOCOL://PATHINNER   ("PROTOCOL" type)
id:ID                  ("id" type)
#CUSTOM-ID             ("custom-id" type)
(CODEREF)              ("coderef" type)
FUZZY                  ("fuzzy" type)
  #+end_example
  - FILENAME :: A string representing an absolute or relative file path.
  - PROTOCOL :: A string which is a one of the link type strings in
    ~org-link-parameters~[fn:olp]
  - PATHINNER :: A string consisting of any character besides square brackets.
  - ID :: A string consisting of hexadecimal numbers separated by hyphens.
  - CUSTOM-ID :: A string consisting of any character besides square brackets.
  - CODEREF :: A string consisting of any character besides square brackets.
  - FUZZY :: A string consisting of any character besides square brackets.

+ DESCRIPTION (optional) :: A series of objects enclosed by square
  brackets, consisting of any character but square brackets.  It can
  contain the minimal set of objects as well as [[#Export_Snippets][export snippets]],
  [[#Inline_Babel_Calls][inline babel calls]], [[#Source_Blocks][inline source blocks]], [[#Macros][macros]], and [[#Statistics_Cookies][statistics
  cookies]].  It can also contain another link, but only when it is a
  plain or angle link.

*Examples*

#+begin_example
[[https://orgmode.org][The Org project homepage]]
[[file:orgmanual.org]]
[[Regular links]]
#+end_example

** Macros
:PROPERTIES:
:CUSTOM_ID: Macros
:END:

Macros are structured according to one of the following patterns:

#+begin_example
{{{NAME}}}
{{{NAME(ARGUMENTS)}}}
#+end_example

+ NAME :: A string starting with a alphabetic character followed by
  any number of alphanumeric characters, hyphens and underscores (=-_=).
+ ARGUMENTS (optional) :: A string consisting of any characters, so
  long as it does not contain the substring =}}}=.  Values within
  ARGUMENTS are separated by commas.  Non-separating commas have to be
  escaped with a backslash character.

*Examples*

#+begin_example
{{{title}}}
{{{one_arg_macro(1)}}}
{{{two_arg_macro(1, 2)}}}
{{{two_arg_macro(1\,a, 2)}}}
#+end_example

** Targets and Radio Targets
:PROPERTIES:
:CUSTOM_ID: Targets_and_Radio_Targets
:END:

Targets are structured according to the following pattern:

#+begin_example
<<TARGET>>
#+end_example

+ TARGET :: A string containing any character but =<=, =>=, or =\n=.  It
  cannot start or end with a whitespace character.

Radio targets are structured according to the following pattern:

#+begin_example
<<<CONTENTS>>>
#+end_example

+ CONTENTS :: A series of objects from the minimal set, starting and
  ending with a non-whitespace character, and containing any character
  but =<=, =>=, or =\n=.

** Statistics Cookies
:PROPERTIES:
:CUSTOM_ID: Statistics_Cookies
:END:

Statistics cookies are structured according to one of the following patterns:

#+begin_example
[PERCENT%]
[NUM1/NUM2]
#+end_example

+ PERCENT (optional) :: A number.
+ NUM1 (optional) :: A number.
+ NUM2 (optional) :: A number.

** Subscript and Superscript
:PROPERTIES:
:CUSTOM_ID: Subscript_and_Superscript
:END:

Subscripts are structured according to the following pattern:

#+begin_example
CHAR_SCRIPT
#+end_example

Superscripts are structured according to the following pattern:

#+begin_example
CHAR^SCRIPT
#+end_example

+ CHAR :: Any non-whitespace character.
+ SCRIPT :: One of the following constructs:
  - A single asterisk character (=*=).
  - An expression enclosed in curly brackets (={=, =}=), which may itself
    contain balanced curly brackets.
  - An instance of the pattern:
    #+begin_example
SIGN CHARS FINAL
    #+end_example
    With no whitespace between SIGN, CHARS and FINAL.
    + SIGN :: Either a plus sign character (=+=), a minus sign character
      (=-=), or the empty string.
    + CHARS :: Either the empty string, or a string consisting of any
      number of alphanumeric characters, commas, backslashes, and
      dots.
    + FINAL :: An alphanumeric character.

** Table Cells
:PROPERTIES:
:CUSTOM_ID: Table_Cells
:END:

Table cells are structured according to the following pattern:

#+begin_example
CONTENTS SPACES|
#+end_example

+ CONTENTS :: A series of objects not containing the vertical bar
  character (=|=).  It can contain the minimal set of objects,
  [[#Citations][citations]], [[#Export_Snippets][export snippets]], [[#Footnote_References][footnote references]], [[#Links][links]], [[#Macros][macros]],
  [[#Targets_and_Radio_Targets][radio targets]], [[#Targets_and_Radio_Targets][targets]], and [[#Timestamps][timestamps]].
+ SPACES :: A string consisting of zero or more of space characters,
  used to align the table columns.

The final vertical bar (=|=) may be omitted in the last cell of a row.

** Timestamps
:PROPERTIES:
:CUSTOM_ID: Timestamps
:END:

Timestamps are structured according to one of the seven following patterns:

#+begin_example
<%%(SEXP)>                                                     (diary)
<DATE TIME REPEATER-OR-DELAY>                                  (active)
[DATE TIME REPEATER-OR-DELAY]                                  (inactive)
<DATE TIME REPEATER-OR-DELAY>--<DATE TIME REPEATER-OR-DELAY>   (active range)
<DATE TIME-TIME REPEATER-OR-DELAY>                             (active range)
[DATE TIME REPEATER-OR-DELAY]--[DATE TIME REPEATER-OR-DELAY]   (inactive range)
[DATE TIME-TIME REPEATER-OR-DELAY]                             (inactive range)
#+end_example

+ SEXP :: A string consisting of any characters but =>= and =\n=.
+ DATE :: An instance of the pattern:
  #+begin_example
YYYY-MM-DD DAYNAME
  #+end_example
  - Y, M, D :: A digit.
  - DAYNAME (optional) :: A string consisting of non-whitespace
    characters except =+=, =-=, =]=, =>=, a digit, or =\n=.
+ TIME (optional) :: An instance of the pattern =H:MM= where =H= represents a one to
  two digit number (and can start with =0=), and =M= represents a single
  digit.
+ REPEATER-OR-DELAY (optional) :: An instance of the following pattern:
  #+begin_example
MARK VALUE UNIT
  #+end_example
  Where MARK, VALUE and UNIT are not separated by whitespace characters.
  - MARK :: Either the string =+= (cumulative type), =++= (catch-up type),
    or =.+= (restart type) when forming a repeater, and either =-= (all
    type) or =--= (first type) when forming a warning delay.
  - VALUE :: A number
  - UNIT :: Either the character =h= (hour), =d= (day), =w= (week), =m=
    (month), or =y= (year)

There can be two instances of =REPEATER-OR-DELAY= in the timestamp: one
as a repeater and one as a warning delay.

*Examples*

#+begin_example
<1997-11-03 Mon 19:15>
<%%(diary-float t 4 2)>
[2004-08-24 Tue]--[2004-08-26 Thu]
<2012-02-08 Wed 20:00 ++1d>
<2030-10-05 Sat +1m -3d>
#+end_example

** Text Markup
:PROPERTIES:
:CUSTOM_ID: Emphasis_Markers
:END:

There are six text markup objects, which are all structured according
to the following pattern:

#+begin_example
PRE MARKER CONTENTS MARKER POST
#+end_example

Where /PRE/, MARKER, CONTENTS, MARKER and /POST/ are not separated by
whitespace characters.

+ [[#Special_Tokens][PRE]] :: Either a whitespace character, =-=, =(=, ={=, ='=, ="=, or the beginning
  of a line.
+ MARKER :: A character that determines the object type, as follows:
  - =*=, a /bold/ object,
  - =/=, an /italic/ object,
  - =_= an /underline/ object,
  - ===, a /verbatim/ object,
  - =~=, a /code/ object
  - =+=, a /strike-through/ object.
+ CONTENTS :: An instance of the pattern:
  #+begin_example
BORDER BODY BORDER
  #+end_example
  Where BORDER and BODY are not separated by whitespace.
  - BORDER :: Any non-whitespace character.
  - BODY ::  Either a string (when MARKER represents code or verbatim)
    or a series of objects from the standard set, not spanning more
    than three lines.
+ [[#Special_Tokens][POST]] :: Either a whitespace character, =-=, =.=, =,=, =;=, =:=, =!=, =?=, ='=, =)=, =}=,
  =[=, ="=, or the end of a line.

*Examples*

#+begin_example
Org is a /plaintext markup syntax/ developed with *Emacs* in 2003.
The canonical parser is =org-element.el=, which provides a number of
functions starting with ~org-element-~.
#+end_example

*** Plain Text
:PROPERTIES:
:CUSTOM_ID: Plain_Text
:END:

Any string that doesn't match any other object can be considered a
plain text object.[fn::In ~org-element.el~ plain text objects are
abstracted away to strings for performance reasons.]
Within a plain text object, all whitespace is collapsed to a single
space. For instance, =hello\n there= is equivalent to =hello there=.

* Footnotes

[fn:1] In particular, the parser requires stars at column 0 to be
quoted by a comma when they do not define a heading.

[fn:2] It also means that only headings and sections can be recognized
just by looking at the beginning of the line.  Planning lines and
property drawers can be recognized by looking at one or two lines
above.

As a consequence, using ~org-element-at-point~ or ~org-element-context~
will move up to the parent heading, and parse top-down from there
until context around the original location is found.


#+latex: \appendix
* Appendix

** Summary of changes compared to the current =org-syntax= document
:PROPERTIES:
:CUSTOM_ID: Changes
:END:

+ Rename "Headlines" -> "Headings", since while both forms are
  currently used in the docs a change to consistently use the latter
  seems imminent if delayed by (what looks like) an ongoing wait for
  Bastien's final say
+ Describe patterns with consistent phrasing, "Xs are structured
  according to the following pattern:"
+ Describe string patterns with consistent phrasing,"a string
  constituted of" (and other forms) -> "a string consisting of"
+ Describe components of a pattern using description lists
+ Use verbatim objects for verbatim text over quotes
+ Change the way inlinetasks are described
+ Add =CONTENTS= component to the Item structure
+ Some whitespace/capitalisation changes
+ (Lots of) miscellaneous wording changes for clarity
+ Fix some minor errors (like referencing a variable which was removed
  7y ago, or saying that switches in source block headers should be
  separated by blank lines)
+ Change the babel call element syntax description to the more detailed form
  found in the manual
+ Change the inline babel call object syntax description to be
  consistent with the babel call element syntax.  This does not
  precisely match the parser behaviour, but matches a very slight
  subset.  The previous description in some parts matched a superset
  of the parser behaviour, and in other places a subset.
+ Change "Greater Elements" / "Elements" to "Greater Elements"/
  "Lesser Elements"
+ Put all Elements under the new level-1 heading "Elements"
+ Separate list definition into four sub-definitions
+ Add a  "Terminology and conventions" section
+ Mention ~plain-text~ objects (see src_elisp{(org-element-type
  "text")}) for the sake of consistency (When something can "contain
  an object" it can contain unformatted text. Without naming
  ~plain-text~ as an object this is a bit funky).
+ Specify that whitespace in plain text is semantically
  collapsed/equivalent to a single space. It is worth noting that this
  is not indicated by =org-element='s parsing, which grabs all the
  whitespace as-is.  However, this feels like something which is done
  for performance reasons, instead of a deliberate choice to make
  whitespace significant, and there are a few things which reinforce
  this view
  - =ox-ascii=, the only export backend to a format which doesn't itself
    collapse whitespace when interpreted, re-fills paragraphs and
    collapses whitespace.
  - We have a line break object.  If =\n= was significant in plain text
    this would be unnecessary.
  - ~org-fill-paragraph~ collapses whitespace
  - Lastly, this is well-established sensible behaviour in every other
    plaintext format that I can think of (HTML, LaTeX, Markdown, reST,
    etc.).
+ Added bunch of examples
+ Probably a few bits and pieces that have slipped my mind.

#+latex: \newpage

** Org Entities
:PROPERTIES:
:CUSTOM_ID: Entities_List
:END:

#+begin_src emacs-lisp :results raw :exports results
(concat "| Name | Character |\n|-\n"
        (mapconcat
         (lambda (entity)
           (if (stringp entity)
               (format "| %s | |"
                       (cond
                        ((string-match-p "^\\*\\*" entity)
                         (upcase (replace-regexp-in-string "^\\*+ " "" entity)))
                        ((string-match-p "^\\*" entity)
                         (replace-regexp-in-string "^\\*+ \\(.+\\)$" "/\\1/" entity))
                        (t entity)))
             (format "| =%s= | \\%s{} |"
                     (car entity)
                     (car entity))))
         org-entities
         "\n"))
#+end_src

#+attr_latex: :environment longtable :font \small
#+RESULTS:
| Name                        | Character                |
|-----------------------------+--------------------------|
| /Letters/                     |                          |
| LATIN                       |                          |
| =Agrave=                      | \Agrave{}                        |
| =agrave=                      | \agrave{}                        |
| =Aacute=                      | \Aacute{}                        |
| =aacute=                      | \aacute{}                        |
| =Acirc=                       | \Acirc{}                        |
| =acirc=                       | \acirc{}                        |
| =Amacr=                       | \Amacr{}                        |
| =amacr=                       | \amacr{}                        |
| =Atilde=                      | \Atilde{}                        |
| =atilde=                      | \atilde{}                        |
| =Auml=                        | \Auml{}                        |
| =auml=                        | \auml{}                        |
| =Aring=                       | \Aring{}                        |
| =AA=                          | \AA{}                        |
| =aring=                       | \aring{}                        |
| =AElig=                       | \AElig{}                        |
| =aelig=                       | \aelig{}                        |
| =Ccedil=                      | \Ccedil{}                        |
| =ccedil=                      | \ccedil{}                        |
| =Egrave=                      | \Egrave{}                        |
| =egrave=                      | \egrave{}                        |
| =Eacute=                      | \Eacute{}                        |
| =eacute=                      | \eacute{}                        |
| =Ecirc=                       | \Ecirc{}                        |
| =ecirc=                       | \ecirc{}                        |
| =Euml=                        | \Euml{}                        |
| =euml=                        | \euml{}                        |
| =Igrave=                      | \Igrave{}                        |
| =igrave=                      | \igrave{}                        |
| =Iacute=                      | \Iacute{}                        |
| =iacute=                      | \iacute{}                        |
| =Idot=                        | \Idot{}                        |
| =inodot=                      | \inodot{}                        |
| =Icirc=                       | \Icirc{}                        |
| =icirc=                       | \icirc{}                        |
| =Iuml=                        | \Iuml{}                        |
| =iuml=                        | \iuml{}                        |
| =Ntilde=                      | \Ntilde{}                        |
| =ntilde=                      | \ntilde{}                        |
| =Ograve=                      | \Ograve{}                        |
| =ograve=                      | \ograve{}                        |
| =Oacute=                      | \Oacute{}                        |
| =oacute=                      | \oacute{}                        |
| =Ocirc=                       | \Ocirc{}                        |
| =ocirc=                       | \ocirc{}                        |
| =Otilde=                      | \Otilde{}                        |
| =otilde=                      | \otilde{}                        |
| =Ouml=                        | \Ouml{}                        |
| =ouml=                        | \ouml{}                        |
| =Oslash=                      | \Oslash{}                        |
| =oslash=                      | \oslash{}                        |
| =OElig=                       | \OElig{}                        |
| =oelig=                       | \oelig{}                        |
| =Scaron=                      | \Scaron{}                        |
| =scaron=                      | \scaron{}                        |
| =szlig=                       | \szlig{}                        |
| =Ugrave=                      | \Ugrave{}                        |
| =ugrave=                      | \ugrave{}                        |
| =Uacute=                      | \Uacute{}                        |
| =uacute=                      | \uacute{}                        |
| =Ucirc=                       | \Ucirc{}                        |
| =ucirc=                       | \ucirc{}                        |
| =Uuml=                        | \Uuml{}                        |
| =uuml=                        | \uuml{}                        |
| =Yacute=                      | \Yacute{}                        |
| =yacute=                      | \yacute{}                        |
| =Yuml=                        | \Yuml{}                        |
| =yuml=                        | \yuml{}                        |
| LATIN (SPECIAL FACE)        |                          |
| =fnof=                        | \fnof{}                        |
| =real=                        | \real{}                        |
| =image=                       | \image{}                        |
| =weierp=                      | \weierp{}                        |
| =ell=                         | \ell{}                        |
| =imath=                       | \imath{}                        |
| =jmath=                       | \jmath{}                        |
| GREEK                       |                          |
| =Alpha=                       | \Alpha{}                        |
| =alpha=                       | \alpha{}                        |
| =Beta=                        | \Beta{}                        |
| =beta=                        | \beta{}                        |
| =Gamma=                       | \Gamma{}                        |
| =gamma=                       | \gamma{}                        |
| =Delta=                       | \Delta{}                        |
| =delta=                       | \delta{}                        |
| =Epsilon=                     | \Epsilon{}                        |
| =epsilon=                     | \epsilon{}                        |
| =varepsilon=                  | \varepsilon{}                        |
| =Zeta=                        | \Zeta{}                        |
| =zeta=                        | \zeta{}                        |
| =Eta=                         | \Eta{}                        |
| =eta=                         | \eta{}                        |
| =Theta=                       | \Theta{}                        |
| =theta=                       | \theta{}                        |
| =thetasym=                    | \thetasym{}                        |
| =vartheta=                    | \vartheta{}                        |
| =Iota=                        | \Iota{}                        |
| =iota=                        | \iota{}                        |
| =Kappa=                       | \Kappa{}                        |
| =kappa=                       | \kappa{}                        |
| =Lambda=                      | \Lambda{}                        |
| =lambda=                      | \lambda{}                        |
| =Mu=                          | \Mu{}                        |
| =mu=                          | \mu{}                        |
| =nu=                          | \nu{}                        |
| =Nu=                          | \Nu{}                        |
| =Xi=                          | \Xi{}                        |
| =xi=                          | \xi{}                        |
| =Omicron=                     | \Omicron{}                        |
| =omicron=                     | \omicron{}                        |
| =Pi=                          | \Pi{}                        |
| =pi=                          | \pi{}                        |
| =Rho=                         | \Rho{}                        |
| =rho=                         | \rho{}                        |
| =Sigma=                       | \Sigma{}                        |
| =sigma=                       | \sigma{}                        |
| =sigmaf=                      | \sigmaf{}                        |
| =varsigma=                    | \varsigma{}                        |
| =Tau=                         | \Tau{}                        |
| =Upsilon=                     | \Upsilon{}                        |
| =upsih=                       | \upsih{}                        |
| =upsilon=                     | \upsilon{}                        |
| =Phi=                         | \Phi{}                        |
| =phi=                         | \phi{}                        |
| =varphi=                      | \varphi{}                        |
| =Chi=                         | \Chi{}                        |
| =chi=                         | \chi{}                        |
| =acutex=                      | \acutex{}                |
| =Psi=                         | \Psi{}                        |
| =psi=                         | \psi{}                        |
| =tau=                         | \tau{}                        |
| =Omega=                       | \Omega{}                        |
| =omega=                       | \omega{}                        |
| =piv=                         | \piv{}                        |
| =varpi=                       | \varpi{}                        |
| =partial=                     | \partial{}                        |
| HEBREW                      |                          |
| =alefsym=                     | \alefsym{}                        |
| =aleph=                       | \aleph{}                        |
| =gimel=                       | \gimel{}                        |
| =beth=                        | \beth{}                        |
| =dalet=                       | \dalet{}                        |
| ICELANDIC                   |                          |
| =ETH=                         | \ETH{}                        |
| =eth=                         | \eth{}                        |
| =THORN=                       | \THORN{}                        |
| =thorn=                       | \thorn{}                        |
| /Punctuation/                 |                          |
| DOTS AND MARKS              |                          |
| =dots=                        | \dots{}                        |
| =cdots=                       | \cdots{}                        |
| =hellip=                      | \hellip{}                        |
| =middot=                      | \middot{}                        |
| =iexcl=                       | \iexcl{}                        |
| =iquest=                      | \iquest{}                        |
| DASH-LIKE                   |                          |
| =shy=                         | \shy{}                   |
| =ndash=                       | \ndash{}                        |
| =mdash=                       | \mdash{}                        |
| QUOTATIONS                  |                          |
| =quot=                        | \quot{}                        |
| =acute=                       | \acute{}                        |
| =ldquo=                       | \ldquo{}                        |
| =rdquo=                       | \rdquo{}                        |
| =bdquo=                       | \bdquo{}                        |
| =lsquo=                       | \lsquo{}                        |
| =rsquo=                       | \rsquo{}                        |
| =sbquo=                       | \sbquo{}                        |
| =laquo=                       | \laquo{}                        |
| =raquo=                       | \raquo{}                        |
| =lsaquo=                      | \lsaquo{}                        |
| =rsaquo=                      | \rsaquo{}                        |
| /Other/                       |                          |
| MISC. (OFTEN USED)          |                          |
| =circ=                        | \circ{}                        |
| =vert=                        | \vert{}                        |
| =vbar=                        | \vbar{}                        |
| =brvbar=                      | \brvbar{}                        |
| =S=                           | \S{}                        |
| =sect=                        | \sect{}                        |
| =amp=                         | \amp{}                        |
| =lt=                          | \lt{}                        |
| =gt=                          | \gt{}                        |
| =tilde=                       | \tilde{}                        |
| =slash=                       | \slash{}                        |
| =plus=                        | \plus{}                        |
| =under=                       | \under{}                        |
| =equal=                       | \equal{}                        |
| =asciicirc=                   | \asciicirc{}                        |
| =dagger=                      | \dagger{}                        |
| =dag=                         | \dag{}                        |
| =Dagger=                      | \Dagger{}                        |
| =ddag=                        | \ddag{}                        |
| WHITESPACE                  |                          |
| =nbsp=                        | \nbsp{}                        |
| =ensp=                        | \ensp{}                        |
| =emsp=                        | \emsp{}                        |
| =thinsp=                      | \thinsp{}                        |
| CURRENCY                    |                          |
| =curren=                      | \curren{}                        |
| =cent=                        | \cent{}                        |
| =pound=                       | \pound{}                        |
| =yen=                         | \yen{}                        |
| =euro=                        | \euro{}                        |
| =EUR=                         | \EUR{}                        |
| =dollar=                      | \dollar{}                        |
| =USD=                         | \USD{}                        |
| PROPERTY MARKS              |                          |
| =copy=                        | \copy{}                        |
| =reg=                         | \reg{}                        |
| =trade=                       | \trade{}                        |
| SCIENCE ET AL.              |                          |
| =minus=                       | \minus{}                        |
| =pm=                          | \pm{}                        |
| =plusmn=                      | \plusmn{}                        |
| =times=                       | \times{}                        |
| =frasl=                       | \frasl{}                        |
| =colon=                       | \colon{}                        |
| =div=                         | \div{}                        |
| =frac12=                      | \frac12{}                        |
| =frac14=                      | \frac14{}                        |
| =frac34=                      | \frac34{}                        |
| =permil=                      | \permil{}                        |
| =sup1=                        | \sup1{}                        |
| =sup2=                        | \sup2{}                        |
| =sup3=                        | \sup3{}                        |
| =radic=                       | \radic{}                        |
| =sum=                         | \sum{}                        |
| =prod=                        | \prod{}                        |
| =micro=                       | \micro{}                        |
| =macr=                        | \macr{}                        |
| =deg=                         | \deg{}                        |
| =prime=                       | \prime{}                        |
| =Prime=                       | \Prime{}                        |
| =infin=                       | \infin{}                        |
| =infty=                       | \infty{}                        |
| =prop=                        | \prop{}                        |
| =propto=                      | \propto{}                        |
| =not=                         | \not{}                        |
| =neg=                         | \neg{}                        |
| =land=                        | \land{}                        |
| =wedge=                       | \wedge{}                        |
| =lor=                         | \lor{}                        |
| =vee=                         | \vee{}                        |
| =cap=                         | \cap{}                        |
| =cup=                         | \cup{}                        |
| =smile=                       | \smile{}                        |
| =frown=                       | \frown{}                        |
| =int=                         | \int{}                        |
| =therefore=                   | \therefore{}                        |
| =there4=                      | \there4{}                        |
| =because=                     | \because{}                        |
| =sim=                         | \sim{}                        |
| =cong=                        | \cong{}                        |
| =simeq=                       | \simeq{}                        |
| =asymp=                       | \asymp{}                        |
| =approx=                      | \approx{}                        |
| =ne=                          | \ne{}                        |
| =neq=                         | \neq{}                        |
| =equiv=                       | \equiv{}                        |
| =triangleq=                   | \triangleq{}                        |
| =le=                          | \le{}                        |
| =leq=                         | \leq{}                        |
| =ge=                          | \ge{}                        |
| =geq=                         | \geq{}                        |
| =lessgtr=                     | \lessgtr{}                        |
| =lesseqgtr=                   | \lesseqgtr{}                        |
| =ll=                          | \ll{}                        |
| =Ll=                          | \Ll{}                        |
| =lll=                         | \lll{}                        |
| =gg=                          | \gg{}                        |
| =Gg=                          | \Gg{}                        |
| =ggg=                         | \ggg{}                        |
| =prec=                        | \prec{}                        |
| =preceq=                      | \preceq{}                        |
| =preccurlyeq=                 | \preccurlyeq{}                        |
| =succ=                        | \succ{}                        |
| =succeq=                      | \succeq{}                        |
| =succcurlyeq=                 | \succcurlyeq{}                        |
| =sub=                         | \sub{}                        |
| =subset=                      | \subset{}                        |
| =sup=                         | \sup{}                        |
| =supset=                      | \supset{}                        |
| =nsub=                        | \nsub{}                        |
| =sube=                        | \sube{}                        |
| =nsup=                        | \nsup{}                        |
| =supe=                        | \supe{}                        |
| =setminus=                    | \setminus{}                        |
| =forall=                      | \forall{}                        |
| =exist=                       | \exist{}                        |
| =exists=                      | \exists{}                        |
| =nexist=                      | \nexist{}                        |
| =nexists=                     | \nexists{}                        |
| =empty=                       | \empty{}                        |
| =emptyset=                    | \emptyset{}                        |
| =isin=                        | \isin{}                        |
| =in=                          | \in{}                        |
| =notin=                       | \notin{}                        |
| =ni=                          | \ni{}                        |
| =nabla=                       | \nabla{}                        |
| =ang=                         | \ang{}                        |
| =angle=                       | \angle{}                        |
| =perp=                        | \perp{}                        |
| =parallel=                    | \parallel{}                        |
| =sdot=                        | \sdot{}                        |
| =cdot=                        | \cdot{}                        |
| =lceil=                       | \lceil{}                        |
| =rceil=                       | \rceil{}                        |
| =lfloor=                      | \lfloor{}                        |
| =rfloor=                      | \rfloor{}                        |
| =lang=                        | \lang{}                        |
| =rang=                        | \rang{}                        |
| =langle=                      | \langle{}                        |
| =rangle=                      | \rangle{}                        |
| =hbar=                        | \hbar{}                        |
| =mho=                         | \mho{}                        |
| ARROWS                      |                          |
| =larr=                        | \larr{}                        |
| =leftarrow=                   | \leftarrow{}                        |
| =gets=                        | \gets{}                        |
| =lArr=                        | \lArr{}                        |
| =Leftarrow=                   | \Leftarrow{}                        |
| =uarr=                        | \uarr{}                        |
| =uparrow=                     | \uparrow{}                        |
| =uArr=                        | \uArr{}                        |
| =Uparrow=                     | \Uparrow{}                        |
| =rarr=                        | \rarr{}                        |
| =to=                          | \to{}                        |
| =rightarrow=                  | \rightarrow{}                        |
| =rArr=                        | \rArr{}                        |
| =Rightarrow=                  | \Rightarrow{}                        |
| =darr=                        | \darr{}                        |
| =downarrow=                   | \downarrow{}                        |
| =dArr=                        | \dArr{}                        |
| =Downarrow=                   | \Downarrow{}                        |
| =harr=                        | \harr{}                        |
| =leftrightarrow=              | \leftrightarrow{}                        |
| =hArr=                        | \hArr{}                        |
| =Leftrightarrow=              | \Leftrightarrow{}                        |
| =crarr=                       | \crarr{}                        |
| =hookleftarrow=               | \hookleftarrow{}                        |
| FUNCTION NAMES              |                          |
| =arccos=                      | \arccos{}                |
| =arcsin=                      | \arcsin{}                |
| =arctan=                      | \arctan{}                |
| =arg=                         | \arg{}                   |
| =cos=                         | \cos{}                   |
| =cosh=                        | \cosh{}                  |
| =cot=                         | \cot{}                   |
| =coth=                        | \coth{}                  |
| =csc=                         | \csc{}                   |
| =deg=                         | \deg{}                        |
| =det=                         | \det{}                   |
| =dim=                         | \dim{}                   |
| =exp=                         | \exp{}                   |
| =gcd=                         | \gcd{}                   |
| =hom=                         | \hom{}                   |
| =inf=                         | \inf{}                   |
| =ker=                         | \ker{}                   |
| =lg=                          | \lg{}                    |
| =lim=                         | \lim{}                   |
| =liminf=                      | \liminf{}                |
| =limsup=                      | \limsup{}                |
| =ln=                          | \ln{}                    |
| =log=                         | \log{}                   |
| =max=                         | \max{}                   |
| =min=                         | \min{}                   |
| =Pr=                          | \Pr{}                    |
| =sec=                         | \sec{}                   |
| =sin=                         | \sin{}                   |
| =sinh=                        | \sinh{}                  |
| =sup=                         | \sup{}                        |
| =tan=                         | \tan{}                   |
| =tanh=                        | \tanh{}                  |
| SIGNS & SYMBOLS             |                          |
| =bull=                        | \bull{}                        |
| =bullet=                      | \bullet{}                        |
| =star=                        | \star{}                        |
| =lowast=                      | \lowast{}                        |
| =ast=                         | \ast{}                        |
| =odot=                        | \odot{}                        |
| =oplus=                       | \oplus{}                        |
| =otimes=                      | \otimes{}                        |
| =check=                       | \check{}                        |
| =checkmark=                   | \checkmark{}                        |
| MISCELLANEOUS (SELDOM USED) |                          |
| =para=                        | \para{}                        |
| =ordf=                        | \ordf{}                        |
| =ordm=                        | \ordm{}                        |
| =cedil=                       | \cedil{}                        |
| =oline=                       | \oline{}                        |
| =uml=                         | \uml{}                        |
| =zwnj=                        | \zwnj{}                         |
| =zwj=                         | \zwj{}                         |
| =lrm=                         | \lrm{}                         |
| =rlm=                         | \rlm{}                         |
| SMILIES                     |                          |
| =smiley=                      | \smiley{}                        |
| =blacksmile=                  | \blacksmile{}                        |
| =sad=                         | \sad{}                        |
| =frowny=                      | \frowny{}                        |
| SUITS                       |                          |
| =clubs=                       | \clubs{}                        |
| =clubsuit=                    | \clubsuit{}                        |
| =spades=                      | \spades{}                        |
| =spadesuit=                   | \spadesuit{}                        |
| =hearts=                      | \hearts{}                        |
| =heartsuit=                   | \heartsuit{}                        |
| =diams=                       | \diams{}                        |
| =diamondsuit=                 | \diamondsuit{}                        |
| =diamond=                     | \diamond{}                        |
| =Diamond=                     | \Diamond{}                        |
| =loz=                         | \loz{}                        |
| =_ =                        | \_ {}                    |
| =_  =                       | \_  {}                   |
| =_   =                      | \_   {}                  |
| =_    =                     | \_    {}                 |
| =_     =                    | \_     {}                |
| =_      =                   | \_      {}               |
| =_       =                  | \_       {}              |
| =_        =                 | \_        {}             |
| =_         =                | \_         {}            |
| =_          =               | \_          {}           |
| =_           =              | \_           {}          |
| =_            =             | \_            {}         |
| =_             =            | \_             {}        |
| =_              =           | \_              {}       |
| =_               =          | \_               {}      |
| =_                =         | \_                {}     |
| =_                 =        | \_                 {}    |
| =_                  =       | \_                  {}   |
| =_                   =      | \_                   {}  |
| =_                    =     | \_                    {} |