Named output formats

The --output-format (or --format) command-line switch can be used to override the default format for how values are printed on the standard output. This format is used for values printed by the read-eval-print interactive interface. It is also used to control how values are printed when Kawa evaluates a file named on the command line (using the -f flag or a just a script name). (It also effects applications compiled with the --main flag.) It currently effects how values are printed by a load, though that may change.

The default format depends on the current programming language. For Scheme, the default is --scheme for read-eval-print interaction, and --ignore for files that are loaded.

The formats currently supported include the following:

scheme: Values are printed in a format matching the Scheme programming language, as if using display. "Groups" or "elements" are written as lists.
readable-scheme: Like scheme, as if using write: Values are generally printed in a way that they can be read back by a Scheme reader. For example, strings have quotation marks, and character values are written like ‘#\A’.
elisp: Values are printed in a format matching the Emacs Lisp programming language. Mostly the same as scheme.
readable-elisp: Like elisp, but values are generally printed in a way that they can be read back by an Emacs Lisp reader. For example, strings have quotation marks, and character values are written like ‘?A’.
clisp
commonlisp: Values are printed in a format matching the Common Lisp programming language, as if written by princ. Mostly the same as scheme.
readable-clisp
readable-commonlisp: Like clisp, but as if written by prin1: values are generally printed in a way that they can be read back by a Common Lisp reader. For example, strings have quotation marks, and character values are written like ‘#\A’.
xml: Values are printed in XML format. "Groups" or "elements" are written as using xml element syntax. Plain characters (such as ‘<’) are escaped (such as ‘<’).
xhtml: Same as xml, but follows the xhtml compatibility guidelines.
html: Values are printed in HTML format. Mostly same as xml format, but certain element without body, are written without a closing tag. For example <img> is written without </img>, which would be illegal for html, but required for xml. Plain characters (such as ‘<’) are not escaped inside <script> or <style> elements.
cgi: The output should be a follow the CGI standards. I.e. assume that this script is invoked by a web server as a CGI script/program, and that the output should start with some response header, followed by the actual response data. To generate the response headers, use the response-header function. If the Content-type response header has not been specified, and it is required by the CGI standard, Kawa will attempt to infer an appropriate Content-ty[e depending on the following value.
ignore: Top-level values are ignored, instead of printed.