| [ << ] | [ < ] | [ Up ] | [ > ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
4.1.2 Literal expressions
- syntax: quote <datum>
- syntax: '<datum>
- syntax: <constant>
‘(quote <datum>)’ evaluates to <datum>. <Datum> may be any external representation of a Scheme object (see section External representations). This notation is used to include literal constants in Scheme code.
(quote a) ⇒ a (quote #(a b c)) ⇒ #(a b c) (quote (+ 1 2)) ⇒ (+ 1 2)
‘(quote <datum>)’ may be abbreviated as ’<datum>. The two notations are equivalent in all respects.
'a ⇒ a '#(a b c) ⇒ #(a b c) '() ⇒ () '(+ 1 2) ⇒ (+ 1 2) '(quote a) ⇒ (quote a) ''a ⇒ (quote a)
Numerical constants, string constants, character constants, and boolean constants evaluate “to themselves”; they need not be quoted.
'"abc" ⇒ "abc" "abc" ⇒ "abc" '145932 ⇒ 145932 145932 ⇒ 145932 '#t ⇒ #t #t ⇒ #t
As noted in section Storage model, it is an error to alter a constant (i.e. the value of a literal expression) using a mutation procedure like ‘set-car!’ or ‘string-set!’.
| [ << ] | [ < ] | [ Up ] | [ > ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
This document was generated on March 31, 2014 using texi2html 5.0.