an error is signalled.
@var{Environment} is used to look up the values of control variables
-such as @samp{*parser-radix*} (@pxref{reader-controls}). If not
+such as @code{param:parser-radix} (@pxref{reader-controls}). If not
supplied, it defaults to the @acronym{REP} environment.
@end deffn
@anchor{reader-controls}
@subsection Reader Controls
-The following names control the behavior of the @code{read} procedure.
-They are looked up in the environment that is passed to @code{read},
-and so may have different values in different environments. The
-global parameters may be dynamically bound by @code{parameterize}, but
-should not be mutated. Make persistent, local changes by shadowing
-the global bindings in the local environment and assigning new
-parameters to them.
+The following parameters control the behavior of the @code{read}
+procedure. They are looked up in the environment that is passed to
+@code{read}, and so may have different values in different
+environments. The global parameters may be dynamically bound by
+@code{parameterize}, but should not be mutated. Make persistent,
+local changes by shadowing the global bindings in the local
+environment and assigning new parameters to them.
-@defvr variable *parser-radix*
+@defvr parameter param:parser-radix
This parameter defines the radix used by the reader when it parses
numbers. This is similar to passing a radix argument to
@code{string->number}. The value of the parameter must be one of
-@code{2}, @code{8}, @code{10}, or @code{16}; any other value is ignored,
-and the reader uses radix @code{10}.
+@code{2}, @code{8}, @code{10}, or @code{16}; an error is signaled if
+the parameter is bound to any other value.
Note that much of the number syntax is invalid for radixes other than
@code{10}. The reader detects cases where such invalid syntax is used
and signals an error. However, problems can still occur when
-@code{*parser-radix*} is set to @code{16}, because syntax that normally
-denotes symbols can now denote numbers (e.g.@: @code{abc}). Because of
-this, it is usually undesirable to set this parameter to anything other
-than the default.
+@code{param:parser-radix} is bound to @code{16}, because syntax that
+normally denotes symbols can now denote numbers (e.g.@: @code{abc}).
+Because of this, it is usually undesirable to bind this parameter to
+anything other than the default.
The default value of this parameter is @code{10}.
@end defvr
-@defvr variable *parser-canonicalize-symbols?*
+@defvr variable *parser-radix*
+This variable is @strong{deprecated}; use @code{param:parser-radix}
+instead.
+@end defvr
+
+@defvr parameter param:parser-canonicalize-symbols?
This parameter controls how the parser handles case-sensitivity of
symbols. If it is bound to its default value of @code{#t}, symbols read
by the parser are converted to lower case before being interned.
Scheme runtime that depend on case-insensitive symbols.
@end defvr
+@defvr variable *parser-canonicalize-symbols?*
+This variable is @strong{deprecated}; use
+@code{param:parser-canonicalize-symbols?} instead.
+@end defvr
+
@node Output Procedures, Format, Input Procedures, Input/Output
@section Output Procedures
@cindex output procedures
The following variables may be dynamically bound to change the behavior
of the @code{write} and @code{display} procedures.
-@defvr variable *unparser-radix*
+@defvr parameter param:unparser-radix
This parameter specifies the default radix used to print numbers. Its
value must be one of the exact integers @code{2}, @code{8}, @code{10},
-or @code{16}; the default is @code{10}. If @code{*unparser-radix*} is
-not @code{10}, numbers are prefixed to indicate their radix.
+or @code{16}; the default is @code{10}. For values other than
+@code{10}, numbers are prefixed to indicate their radix.
@end defvr
-@defvr variable *unparser-list-breadth-limit*
+@defvr variable *unparser-radix*
+This variable is @strong{deprecated}; use @code{param:unparser-radix}
+instead.
+@end defvr
+
+@defvr parameter param:unparser-list-breadth-limit
This parameter specifies a limit on the length of the printed
representation of a list or vector; for example, if the limit is
@code{4}, only the first four elements of any list are printed, followed
@example
@group
-(parameterize ((*unparser-list-breadth-limit* 4))
+(parameterize ((param:unparser-list-breadth-limit 4))
(lambda ()
(write-to-string '(a b c d))))
@result{} "(a b c d)"
-(parameterize ((*unparser-list-breadth-limit* 4))
+(parameterize ((param:unparser-list-breadth-limit 4))
(lambda ()
(write-to-string '(a b c d e))))
@result{} "(a b c d ...)"
@end example
@end defvr
-@defvr variable *unparser-list-depth-limit*
+@defvr variable *unparser-list-breadth-limit*
+This variable is @strong{deprecated}; use
+@code{param:unparser-list-breadth-limit} instead.
+@end defvr
+
+@defvr parameter param:unparser-list-depth-limit
This parameter specifies a limit on the nesting of lists and vectors in
the printed representation. If lists (or vectors) are more deeply
nested than the limit, the part of the representation that exceeds the
@example
@group
-(parameterize((*unparser-list-depth-limit* 4))
+(parameterize ((param:unparser-list-depth-limit 4))
(lambda ()
(write-to-string '((((a))) b c d))))
@result{} "((((a))) b c d)"
-(parameterize ((*unparser-list-depth-limit* 4))
+(parameterize ((param:unparser-list-depth-limit 4))
(lambda ()
(write-to-string '(((((a)))) b c d))))
@result{} "((((...))) b c d)"
@end example
@end defvr
-@defvr variable *unparser-string-length-limit*
+@defvr variable *unparser-list-depth-limit*
+This variable is @strong{deprecated}; use
+@code{param:unparser-list-depth-limit} instead.
+@end defvr
+
+@defvr parameter param:unparser-string-length-limit
This parameter specifies a limit on the length of the printed
representation of strings. If a string's length exceeds this limit, the
part of the printed representation for the characters exceeding the
@example
@group
-(parameterize ((*unparser-string-length-limit* 4))
+(parameterize ((param:unparser-string-length-limit 4))
(lambda ()
(write-to-string "abcd")))
@result{} "\"abcd\""
-(parameterize ((*unparser-string-length-limit* 4))
+(parameterize ((param:unparser-string-length-limit 4))
(lambda ()
(write-to-string "abcde")))
@result{} "\"abcd...\""
@end example
@end defvr
-@defvr variable *unparse-with-maximum-readability?*
+@defvr variable *unparser-string-length-limit*
+This variable is @strong{deprecated}; use
+@code{param:unparser-string-length-limit} instead.
+@end defvr
+
+@defvr parameter param:unparse-with-maximum-readability?
This parameter, which takes a boolean value, tells the printer to use a
special printed representation for objects that normally print in a form
that cannot be recognized by @code{read}. These objects are printed
these hash numbers are different for each invocation of Scheme.
@end defvr
+@defvr variable *unparse-with-maximum-readability?*
+This variable is @strong{deprecated}; use
+@code{param:unparse-with-maximum-readability?} instead.
+@end defvr
+
@node Format, Custom Output, Output Procedures, Input/Output
@section Format
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