GENEVA DOCUMENT SPECIFICATION

                                                    Interstellar Ventures
                                              Saturday, 19 September 2015

Table of Contents

   1 Rich Text
   2 Element Types
   3 Formal Definition

   This is a draft standard, this notice will disappear once the
   specification is final.

   A Geneva document is an ordered collection of elements. Geneva defines
   the following element types:

 * Pargraph

 * Listing

 * Table

 * Plaintext

 * Media

 * Section

1 Rich Text

   A central component of all element types is rich text. Rich text is
   defined as a sequence of text tokens, each made up of a variable
   number of character strings and an attribute to signify its
   appearance. There are five different types of text tokens:

     Token           Description                                                   
     plain s         Render s in regular font.                                     
     bold s          Recommends to render s in bold font.                          
     italic s        Recommends to render s in italic font.                        
     fixed-width s   Recommends to render s in fixed-width font.                   
     url s           Interpret s as a Uniform Resource Locator.                    
     url s, u        Interpret u as a Uniform Resource Locator and s as its label. 
   
       Table 1. Text token types.

   The occurrence of whitespace characters in text token strings is
   restricted by the following rules:

 * All whitespace character sequences are to be reduced to a single
   space character (ASCII 0x20 or equivalent).

 * For all token types except the plain type, discard prefixes and
   suffixes of whitespace character sequences.

 * For the first and last text tokens in a rich text sequence, discard
   prefixes and suffixes of whitespace character sequences
   respectively.

   At least the following conceptual characters have to be recognized as
   whitespace:

 * Space

 * Tab

 * Newline (including Carriage Return)

 * Vertical Tab

 * Page break

2 Element Types

   A paragraph consists of exactly one rich text sequence. It signifies a
   self-contained piece of text.

   A listing consists of a finite sequence of rich text sequences. It
   signifies an ordered group of self-contained text pieces.

   A table consists of a two-dimensional matrix of rich text sequences
   and a single rich text sequence being its description. It signifies a
   tabular relation of the matrix of rich text pieces.

   A plaintext element consists of a verbatim character string and a
   single rich text sequence being its description. It signifies a
   sequence of characters which has to be preserved as is except for
   whitespace prefixes and suffixes (including newlines).

   A media element consists of an Unique Resource Locator string and a
   single rich text sequence being its description. It signifies the
   embedment of an external resource.

   A description as mentioned above, is a piece of text elaborating the
   contents of a given element.

   A section consists of a Geneva document and a single rich text
   sequence being its heading. It signifies a continuous subsequence of
   the document, introduced by a headline (the heading).

3 Formal Definition

   The table below defines a Geneva document formally using the modifed
   BNF syntax described in ANSI Common Lisp's Notational Conventions.¹

     Symbol             Expression                                               
     document           document-element*                                        
     document-element   pargraph | listing | table | plaintext | media | section 
     paragraph          text-token+                                              
     listing            rich-text+                                               
     table              rich-text table-row+                                     
     table-row          rich-text+                                               
     plaintext          rich-text string                                         
     media              rich-text string                                         
     section            rich-text document-element*                              
     rich-text          text-token*                                              
     text-token         A text token, see “Rich Text”                            
     string             A character string                                       
   
       Table 2. Formal definition of a Geneva document.

 * 1. ANSI Common Lisp: Notational Conventions
   (http://users-phys.au.dk/harder/Notational-Conventions.html)