►The Racket Reference
▼3 Syntactic Forms
在本页中：
quote
#%datum
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3.3 Literals: quote and #%datum

Many forms are implicitly quoted (via #%datum) as literals. See Expansion Steps for more information.

+引述：quote 与 ' in Racket 指南 introduces quote.

语法

(quote datum)

Produces a constant value corresponding to datum (i.e., the representation of the program fragment) without its lexical information, source location, etc. Quoted pairs, vectors, and boxes are immutable.

Examples:
> (quote x)

'x

> (quote (+ 1 2))

'(+ 1 2)

> (+ 1 2)

3

语法

(#%datum . datum)

Expands to (quote datum), as long as datum is not a keyword. If datum is a keyword, a syntax error is reported.

See also Expansion Steps for information on how the expander introduces #%datum identifiers.

Examples:
> (#%datum . 10)

10

> (#%datum . x)

'x

> (#%datum . #:x)

eval:6:0: #%datum: keyword misused as an expression

  at: #:x

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