BNF Grammar
The complete formal grammar specification for Mark Notation is available in the mark.bnf file.
Interactive Railroad Diagram
For a visual representation of the grammar, you can explore the interactive railroad diagram.
The railroad diagram provides a visual way to understand the grammar structure. You can click on grammar terms to navigate around and see how different parts of the syntax connect together.
Grammar Overview
Below is a snapshot of the top-level grammar structure:
Key Grammar Differences vs. JSON
Root Level
- Mark allows multiple values at root level, separated by ‘;’ or line break
- JSON allows only one value at root level
Elements
element ::= '<' type_name properties contents '>'
type_name ::= identifier | symbol
properties ::= (property ','?)*
property ::= key ':' value
contents ::= (text | binary | json_object | mark_object | mark_pragma)*
Extended Data Types
Mark extends JSON with several new data types:
- Symbol: Single-quoted strings or unquoted identifiers
- Binary: Base64 or hex encoded data in
b'...' - Datetime: ISO 8601 datetime strings in
t'...' - Decimal: Big decimal numbers with ‘n’ suffix
- Comments: Both
//and/* */style comments