Grammar Syntax

Example

$FOO -> /foo  
$FOO -> /foo$FOO  
$FOO -> $BAR  
$BAR -> /bar  
$BAR -> $BAR  

Nonterminals

A Nonterminal starts with a leading $. The nonterminal FOO would be written as:

$FOO

Terminals

A Terminal starts with a leading /. The terminal bar would be written as:

/bar

Note that /ab differs from /a/b. The string /ab resolves to the terminal ab, whereas /a/b resolves to the terminals a and b

Empty String

/~ resolves to the Empty String

Productions

The -> indicates a production, the Nonterminal on it's left side gets replaced by the string of Nonterminals and Terminals on it's right side.

$FOO -> /foo$FOO