2 Syntactic Forms
This section describes the core syntax forms that appear in a fully expanded expression, plus a many closely-related non-core forms. See Fully Expanded Programs for the core grammar.
2.20 Quasiquoting: quasiquote, unquote, and unquote-splicing |
Notation
Each syntactic form is described by a BNF-like notation that describes a combination of (syntax-wrapped) pairs, symbols, and other data (not a sequence of characters). These grammatical specifications are shown as follows:
(some-form id )
Within such specifications,
... indicates zero or more repetitions of the preceding datum.
...+ indicates one or more repetitions of the preceding datum.
italic meta-identifiers play the role of non-terminals; in particular,
a meta-identifier that ends in id stands for an identifier.
a meta-identifier that ends in keyword stands for a keyword.
a meta-identifier that ends with expr stands for a sub-form that is expanded as an expression.
A meta-identifier that ends with body stands for a sub-form that is expanded in an internal-definition context (see Internal Definitions).