[asdf-devel] source file encoding

[Douglas Crosher]

My suggestion is to just use :external-format plus some minimal translations for CLISP to help write portable code, for example
:utf-8 and :iso-8859-1 or :latin1, which should cover most portable CL projects, and to make the default :default.

It is not possible to validate the external-format so the default action should be to pass it through.  With a default of passing it
through, it would seem most appropriate to name it :external-format, and to call any processing a translation.

The external-format is implementation dependent and user extensible which making it impossible for ASDF to validate.  Requiring a
custom ASDF hook to be installed seems an unnecessary burden with no utility.

CL implementations are required to recognise :default as an external-format, and could be expected to have a sensible default for
their environment.  Any other default value is problematic as it may not be supported.  If a project really needs UTF-8 source files
then it would not appear to be a big burden to require this to be specified.  A lot of portable code can be written without needing
UTF-8 source files, even code that supports UNICODE.

> (:file "foo" :external-format :latin1))

Regards
Douglas Crosher