*** empty log message ***

[gnu-emacs] / lispref / streams.texi

diff --git a/lispref/streams.texi b/lispref/streams.texi
index cf3f14a095f819b535284e429dd50ba7797da626..09f8695cd25a11a607033f89ca633dd08bb6ffbb 100644 (file)
--- a/lispref/streams.texi
+++ b/lispref/streams.texi
@@ -1,6 +1,7 @@
 @c -*-texinfo-*-
 @c This is part of the GNU Emacs Lisp Reference Manual.
 @c -*-texinfo-*-
 @c This is part of the GNU Emacs Lisp Reference Manual.

-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1998 Free Software Foundation, Inc. 
+@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1998, 1999
+@c   Free Software Foundation, Inc.

 @c See the file elisp.texi for copying conditions.
 @setfilename ../info/streams
 @node Read and Print, Minibuffers, Debugging, Top
 @c See the file elisp.texi for copying conditions.
 @setfilename ../info/streams
 @node Read and Print, Minibuffers, Debugging, Top


@@ -52,8 +53,8 @@ returns the symbol @code{foo}.  Printing a list whose elements are
 text produces a list (but not the same list) with elements @code{a}
 and @code{b}.
 
 text produces a list (but not the same list) with elements @code{a}
 and @code{b}.
 

-  However, these two operations are not precisely inverses.  There are
-three kinds of exceptions:
+  However, these two operations are not precisely inverse to each other.
+There are three kinds of exceptions:

 
 @itemize @bullet
 @item
 
 @itemize @bullet
 @item


@@ -124,7 +125,13 @@ came from''.  In this case, it makes no difference what value
 @code{t} used as a stream means that the input is read from the
 minibuffer.  In fact, the minibuffer is invoked once and the text
 given by the user is made into a string that is then used as the
 @code{t} used as a stream means that the input is read from the
 minibuffer.  In fact, the minibuffer is invoked once and the text
 given by the user is made into a string that is then used as the

-input stream.
+input stream.  If Emacs is running in batch mode, standard input is used
+instead of the minibuffer.  For example,
+@example
+(message "%s" (read t))
+@end example
+will read a Lisp expression from standard input and print the result
+to standard output.

 
 @item @code{nil}
 @cindex @code{nil} input stream
 
 @item @code{nil}
 @cindex @code{nil} input stream


@@ -331,6 +338,7 @@ For example:
 @defvar standard-input
 This variable holds the default input stream---the stream that
 @code{read} uses when the @var{stream} argument is @code{nil}.
 @defvar standard-input
 This variable holds the default input stream---the stream that
 @code{read} uses when the @var{stream} argument is @code{nil}.

+The default is @code{t}, meaning use the minibuffer.

 @end defvar
 
 @node Output Streams
 @end defvar
 
 @node Output Streams


@@ -354,7 +362,9 @@ The output characters are inserted into the buffer that @var{marker}
 points into, at the marker position.  The marker position advances as
 characters are inserted.  The value of point in the buffer has no effect
 on printing when the stream is a marker, and this kind of printing
 points into, at the marker position.  The marker position advances as
 characters are inserted.  The value of point in the buffer has no effect
 on printing when the stream is a marker, and this kind of printing

-does not move point.
+does not move point (except that if the marker points at or before the
+position of point, point advances with the surrounding text, as
+usual).

 
 @item @var{function}
 @cindex function output stream
 
 @item @var{function}
 @cindex function output stream


@@ -389,11 +399,6 @@ initially located as shown immediately before the @samp{h} in
 
 @cindex print example
 @example
 
 @cindex print example
 @example

-@group
-(setq m (set-marker (make-marker) 10 (get-buffer "foo")))
-     @result{} #<marker at 10 in foo>
-@end group
-

 @group
 ---------- Buffer: foo ----------
 This is t@point{}he contents of foo.
 @group
 ---------- Buffer: foo ----------
 This is t@point{}he contents of foo.


@@ -403,10 +408,6 @@ This is t@point{}he contents of foo.
 (print "This is the output" (get-buffer "foo"))
      @result{} "This is the output"
 
 (print "This is the output" (get-buffer "foo"))
      @result{} "This is the output"
 

-@group
-m
-     @result{} #<marker at 32 in foo>
-@end group

 @group
 ---------- Buffer: foo ----------
 This is t
 @group
 ---------- Buffer: foo ----------
 This is t


@@ -431,8 +432,8 @@ This is the @point{}output
 @end group
 
 @group
 @end group
 
 @group

-m
-     @result{} #<marker at 11 in foo>
+(setq m (copy-marker 10))
+     @result{} #<marker at 10 in foo>

 @end group
 
 @group
 @end group
 
 @group


@@ -450,7 +451,7 @@ he @point{}output
 
 @group
 m
 
 @group
 m

-     @result{} #<marker at 35 in foo>
+     @result{} #<marker at 34 in foo>

 @end group
 @end example
 
 @end group
 @end example
 


@@ -491,7 +492,7 @@ in reverse order.
 
 @group
 last-output
 
 @group
 last-output

-     @result{} (10 34 116 117 112 116 117 111 32 101 104 
+     @result{} (10 34 116 117 112 116 117 111 32 101 104

     116 32 115 105 32 115 105 104 84 34 10)
 @end group
 @end example
     116 32 115 105 32 115 105 104 84 34 10)
 @end group
 @end example


@@ -568,13 +569,12 @@ characters are used.  @code{print} returns @var{object}.  For example:
 (progn (print 'The\ cat\ in)
        (print "the hat")
        (print " came back"))
 (progn (print 'The\ cat\ in)
        (print "the hat")
        (print " came back"))

-     @print{} 
+     @print{}

      @print{} The\ cat\ in
      @print{} The\ cat\ in

-     @print{} 
+     @print{}

      @print{} "the hat"
      @print{} "the hat"

-     @print{} 
+     @print{}

      @print{} " came back"
      @print{} " came back"

-     @print{} 

      @result{} " came back"
 @end group
 @end example
      @result{} " came back"
 @end group
 @end example


@@ -588,8 +588,8 @@ This function outputs the printed representation of @var{object} to
 
 @example
 @group
 
 @example
 @group

-(progn (prin1 'The\ cat\ in) 
-       (prin1 "the hat") 
+(progn (prin1 'The\ cat\ in)
+       (prin1 "the hat")

        (prin1 " came back"))
      @print{} The\ cat\ in"the hat"" came back"
      @result{} " came back"
        (prin1 " came back"))
      @print{} The\ cat\ in"the hat"" came back"
      @result{} " came back"


@@ -659,12 +659,11 @@ characters in the output.  (This argument is supported in Emacs versions
 @end group
 @end example
 
 @end group
 @end example
 

-See @code{format}, in @ref{String Conversion}, for other ways to obtain
+See @code{format}, in @ref{Formatting Strings}, for other ways to obtain

 the printed representation of a Lisp object as a string.
 @end defun
 
 @defmac with-output-to-string body...
 the printed representation of a Lisp object as a string.
 @end defun
 
 @defmac with-output-to-string body...

-@tindex with-output-to-string

 This macro executes the @var{body} forms with @code{standard-output} set
 up to feed output into a string.  Then it returns that string.
 
 This macro executes the @var{body} forms with @code{standard-output} set
 up to feed output into a string.  Then it returns that string.
 


@@ -686,6 +685,14 @@ returns @code{"The buffer is foo"}.
 @defvar standard-output
 The value of this variable is the default output stream---the stream
 that print functions use when the @var{stream} argument is @code{nil}.
 @defvar standard-output
 The value of this variable is the default output stream---the stream
 that print functions use when the @var{stream} argument is @code{nil}.

+The default is @code{t}, meaning display in the echo area.
+@end defvar
+
+@defvar print-quoted
+If this is non-@code{nil}, that means to print quoted forms using
+abbreviated reader syntax.  @code{(quote foo)} prints as @code{'foo},
+@code{(function foo)} as @code{#'foo}, and backquoted forms print
+using modern backquote syntax.

 @end defvar
 
 @defvar print-escape-newlines
 @end defvar
 
 @defvar print-escape-newlines


@@ -723,6 +730,29 @@ In the second expression, the local binding of
 @code{prin1}, but not during the printing of the result.
 @end defvar
 
 @code{prin1}, but not during the printing of the result.
 @end defvar
 

+@defvar print-escape-nonascii
+If this variable is non-@code{nil}, then unibyte non-@acronym{ASCII}
+characters in strings are unconditionally printed as backslash sequences
+by the print functions @code{prin1} and @code{print} that print with
+quoting.
+
+Those functions also use backslash sequences for unibyte non-@acronym{ASCII}
+characters, regardless of the value of this variable, when the output
+stream is a multibyte buffer or a marker pointing into one.
+@end defvar
+
+@defvar print-escape-multibyte
+If this variable is non-@code{nil}, then multibyte non-@acronym{ASCII}
+characters in strings are unconditionally printed as backslash sequences
+by the print functions @code{prin1} and @code{print} that print with
+quoting.
+
+Those functions also use backslash sequences for multibyte
+non-@acronym{ASCII} characters, regardless of the value of this variable,
+when the output stream is a unibyte buffer or a marker pointing into
+one.
+@end defvar
+

 @defvar print-length
 @cindex printing limits
 The value of this variable is the maximum number of elements to print in
 @defvar print-length
 @cindex printing limits
 The value of this variable is the maximum number of elements to print in


@@ -750,3 +780,59 @@ parentheses and brackets when printed.  Any list or vector at a depth
 exceeding this limit is abbreviated with an ellipsis.  A value of
 @code{nil} (which is the default) means no limit.
 @end defvar
 exceeding this limit is abbreviated with an ellipsis.  A value of
 @code{nil} (which is the default) means no limit.
 @end defvar

+
+@defopt eval-expression-print-length
+@defoptx eval-expression-print-level
+These are the values for @code{print-length} and @code{print-level}
+used by @code{eval-expression}, and thus, indirectly, by many
+interactive evaluation commands (@pxref{Lisp Eval,, Evaluating
+Emacs-Lisp Expressions, emacs, The GNU Emacs Manual}).
+@end defopt
+
+  These variables are used for detecting and reporting circular
+and shared structure:
+
+@tindex print-circle
+@defvar print-circle
+If non-@code{nil}, this variable enables detection of circular
+and shared structure in printing.
+@end defvar
+
+@tindex print-gensym
+@defvar print-gensym
+If non-@code{nil}, this variable enables detection of uninterned symbols
+(@pxref{Creating Symbols}) in printing.  When this is enabled,
+uninterned symbols print with the prefix @samp{#:}, which tells the Lisp
+reader to produce an uninterned symbol.
+@end defvar
+
+@defvar print-continuous-numbering
+If non-@code{nil}, that means number continuously across print calls.
+This affects the numbers printed for @samp{#@var{n}=} labels and
+@samp{#@var{m}#} references.
+
+Don't set this variable with @code{setq}; you should only bind it
+temporarily to @code{t} with @code{let}.  When you do that, you should
+also bind @code{print-number-table} to @code{nil}.
+@end defvar
+
+@defvar print-number-table
+This variable holds a vector used internally by printing to implement
+the @code{print-circle} feature.  You should not use it except
+to bind it to @code{nil} when you bind @code{print-continuous-numbering}.
+@end defvar
+
+@defvar float-output-format
+This variable specifies how to print floating point numbers.  Its
+default value is @code{nil}, meaning use the shortest output
+that represents the number without losing information.
+
+To control output format more precisely, you can put a string in this
+variable.  The string should hold a @samp{%}-specification to be used
+in the C function @code{sprintf}.  For further restrictions on what
+you can use, see the variable's documentation string.
+@end defvar
+
+@ignore
+   arch-tag: 07636b8c-c4e3-4735-9e06-2e864320b434
+@end ignore