3.21 Syntax Quoting: quote-syntax

Similar to quote , but produces a syntax object that preserves the lexical information and source-location information attached to datum at expansion time.

When #:local is specified, then all scopes in the syntax object’s lexical information are preserved. When #:local is omitted, then the scope sets within datum are pruned to omit the scope for any binding form that appears between the quote-syntax form and the enclosing top-level context, module body, or phase level crossing, whichever is closer.

Unlike syntax (#'), quote-syntax does not substitute pattern variables bound by with-syntax , syntax-parse , or syntax-case .

Examples:

> (syntax? (quote-syntax x))

#t
> (quote-syntax (123))

#<syntax:eval:78:0 (1 2 3)>

> (with-syntax ([a#'5])
(quote-syntax (abc)))

#<syntax:eval:79:0 (a b c)>

> (free-identifier=? (let ([x1])(quote-syntax x))
(quote-syntax x))

#t

> (free-identifier=? (let ([x1])(quote-syntax x#:local))
(quote-syntax x))

#f

Changed in version 6.3 of package base: Added scope pruning and support for #:local.

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