The following notations are used by the Lexer and Syntax grammar snippets:

CAPITALKW_IF, INTEGER_LITERALA token produced by the lexer
ItalicCamelCaseLetStatement, ItemA syntactical production
stringx, while, *The exact character(s)
\x\n, \r, \t, \0The character represented by this escape
x?pub?An optional item
x*OuterAttribute*0 or more of x
x+MacroMatch+1 or more of x
xa..bHEX_DIGIT1..6a to b repetitions of x
|u8 | u16, Block | ItemEither one or another
[ ][b B]Any of the characters listed
[ - ][a-z]Any of the characters in the range
~[ ]~[b B]Any characters, except those listed
~string~\n, ~*/Any characters, except this sequence
( )(, Parameter)?Groups items

String table productions

Some rules in the grammar — notably unary operators, binary operators, and keywords — are given in a simplified form: as a listing of printable strings. These cases form a subset of the rules regarding the token rule, and are assumed to be the result of a lexical-analysis phase feeding the parser, driven by a DFA, operating over the disjunction of all such string table entries.

When such a string in monospace font occurs inside the grammar, it is an implicit reference to a single member of such a string table production. See tokens for more information.