# DTree file specification
## Notation
This document uses [Extended Backus-Naur Form](https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form).
## Basic definitions
```EBNF
unicode_letter = (* A unicode code point classified as "Letter" *)
unicode_digit = (* A unicode code point classified as "Number, decimal digit" *)
unicode_char = (* Any unicode point *)
letter = unicode_letter | "_"
`asdfaba`
`23193aadf`
`blaher`
Non-Examples
`hello bob`
## Message for a section
Defining a message has the form:
This must take place at the beginning of a line--the `[` must be the first character of the line
```EBNF
section_message = "[", { space }, identifier { space } "]" [ " " { unicode_char } ]
```
Examples
`[asdf] Welcome to party`
`[1913]`
```a
[aaad] Hello \
This is a super dooper thing \
Even with [ characters and all \
```
Non-examples:
```a
[adfa] Hello \
This is pretty cool boi
[
```
Reason: Cannot start a line with `[`
## Mapping for a section
This must take place at the beginning of a line--the `[` must be the first character of the line
```EBNF
mapping = "[" { space } identifier { space } "(" {unicode_char - ")\n"} ")" {space} "->" {space} identifier {space} "]" [ space { unicode_char }]
```
Examples:
```a
[dd (a)->b]
```