Output Printing

MzScheme's printer follows these non-standard rules:

• Boxes can be printed with the #& notation (see section 3.1). When box printing is off, all boxes are printed as #<box>. Box printing is controlled with  print-box; this procedure takes zero arguments to return the current mode, or one Boolean argument to set the mode. Box printing is on by default.

   

• Structures can be printed as vectors. In the vector, the first item is a symbol of the form struct:s -- where s is the name of the structure -- and the remaining elements are the elements of the structure. When structure printing is off, structures are printed as #<struct:s>. Structure printing is controlled with  print-struct; this procedure takes zero arguments to return the current mode, or one Boolean argument to set the mode. Structure printing is off by default.

   

• Symbols containing spaces or special charaters are printed using escaping backslashes and quoting vertical bars. Symbols are quoted with vertical bars when they would otherwise print the same as a numerical constant. See section 3.1.

   

• Characters with the special names described in section 3.1 write using the same name. (Some characters have multiple names; the # newline  and # nul  names are used instead of # linefeed  and # null ). All other charaters write as #   followed by the single-byte character value. All characters display as the single-byte character value.

   

• S-expressions with shared stucture can be printed using #n= and #n#. See section 3.3.