(guile.info.gz) Keyword Read Syntax

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(guile.info.gz) Keywords

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 21.7.3 Keyword Read Syntax
 --------------------------
 
 Guile, by default, only recognizes the keyword syntax specified by R5RS.
 A token of the form `#:NAME', where `NAME' has the same syntax as a
 Scheme symbol ( Symbol Read Syntax), is the external
 representation of the keyword named `NAME'.  Keyword objects print
 using this syntax as well, so values containing keyword objects can be
 read back into Guile.  When used in an expression, keywords are
 self-quoting objects.
 
    If the `keyword' read option is set to `'prefix', Guile also
 recognizes the alternative read syntax `:NAME'.  Otherwise, tokens of
 the form `:NAME' are read as symbols, as required by R5RS.
 
    To enable and disable the alternative non-R5RS keyword syntax, you
 use the `read-set!' procedure documented in  User level options
 interfaces and  Reader options.
 
      (read-set! keywords 'prefix)
 
      #:type
      =>
      #:type
 
      :type
      =>
      #:type
 
      (read-set! keywords #f)
 
      #:type
      =>
      #:type
 
      :type
      -|
      ERROR: In expression :type:
      ERROR: Unbound variable: :type
      ABORT: (unbound-variable)
 

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(guile.info.gz) Coding With Keywords

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(guile.info.gz) Keyword Procedures