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If token is a sequence of two or more digits, then this syntax is
equivalent to #.(integer->char (string->number token 8))
.
If token is C-
, c-
, or ^
followed by a
character, then this syntax is read as a control character. If
token is M-
or m-
followed by a character, then a
meta character is read. c-
and m-
prefixes may be
combined.
If feature is provided?
then form is read as a scheme
expression. If not, then form is treated as whitespace.
Feature is a boolean expression composed of symbols and and
,
or
, and not
of boolean expressions.
For more information on provided?
,
See Require in SLIB.
is equivalent to #+(not feature) expression
.
Is a balanced comment. Everything up to the matching |#
is
ignored by the read
. Nested #|…|#
can occur inside
any thing.
Load sytax is Read syntax enabled for read
only when that
read
is part of loading a file or string. This distinction was
made so that reading from a datafile would not be able to corrupt a
scheme program using ‘#.’.
Is read as the object resulting from the evaluation of expression. This substitution occurs even inside quoted structure.
In order to allow compiled code to work with #.
it is good
practice to define those symbols used inside of expression with
#.(define …)
. For example:
#.(define foo 9) ⇒ #<unspecified> '(#.foo #.(+ foo foo)) ⇒ (9 18)
is equivalent to form (for compatibility with common-lisp).
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