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(librep.info)Output Functions

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Output Functions
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 - Function: write stream data #!optional length
     Writes the specified character(s) to the output stream STREAM.
     DATA is either the character or the string to be written. If DATA
     is a string the optional argument LENGTH may specify how many
     characters are to be written. The value returned is the number of
     characters successfully written.

          (write standard-output "Testing 1.. 2.. 3..")
              -| Testing 1.. 2.. 3..
              => 19

 - Function: copy-stream input-stream output-stream
     This function copies all characters which may be read from
     INPUT-STREAM to OUTPUT-STREAM. The copying process is not stopped
     until the end of the input stream is read. Returns the number of
     characters copied.

     Be warned, if you don't choose the streams carefully you may get a
     deadlock which only an interrupt signal can break!

 - Function: print object #!optional stream
     Outputs a newline character to the output stream STREAM, then
     writes a textual representation of OBJECT to the stream.

     If possible, this representation will be the read syntax of OBJECT.

     OBJECT is returned.

          (print '(1 2 3))
              -|
              -| (1 2 3)
              => (1 2 3)

 - Function: prin1 object #!optional stream
     Similar to `print' but no initial newline is output.

          (prin1 '(1 2 3))
              -| (1 2 3)
              => (1 2 3)
          
          (prin1 '|(xy((z]|)              ;A strange symbol
              -| \(xy\(\(z\]
              => \(xy\(\(z\]

 - Function: prin1-to-string object
     Returns a string containing the characters that `prin1' would
     output when it prints OBJECT.

          (prin1-to-string '(1 2 3))
              => "(1 2 3)"

 - Function: princ object #!optional stream
     Prints a textual representation of OBJECT to the output stream
     STREAM. No steps are taken to create output that `read' can parse;
     in particular, no double-quote characters surround strings.

          (princ "foo")
              -| foo
              => "foo"
          
          (princ '|(xy((z]|)
              -| (xy((z]
              => \(xy\(\(z\]

   Several variables may be used to control how objects are printed.

 - Variable: print-escape
     This defines which control characters `print' and `prin1' will
     escape (using backslashes). Possible values are:

    `()'
          Only escape double-quote and backslash characters.

    `newlines'
          Only escape double-quote, backslash, newline, `TAB', and
          formfeed characters.

    `t'
          Escape double-quote, backslash, and all control characters
          (anything with a numeric value less than 32, or greater than
          126).

 - Variable: print-length
     This variable, if true, limits the number of elements printed from
     lists.

 - Variable: print-level
     This variable, if true, limits the recursion depth when printing
     lists.