This document uses a R-BNF notation, which is a mix of Extended BNF and PCRE-style regular expressions:

Rules are in the form: name = definition. Rule names referenced as-is in the definition. Angle brackets may be used to help facilitate discerning the use of rule names.

Literals are surrounded by quotation marks: "literal".

Sequences: (rule1 rule2) or simply rule1 rule2.

Alternatives groups: (rule1 | rule2).

Optional groups: [rule[]].

Repetition: rule* means 0 or more of this rule or this group.

Repetition: rule+ means 1 or more of this rule or this group.