```
 xj9% unsweeten --help
Backtrace:
In ice-9/boot-9.scm:
  1755:12 10 (with-exception-handler _ _ #:unwind? _ # _)
In unknown file:
           9 (apply-smob/0 #<thunk 7fffe9914300>)
In ice-9/boot-9.scm:
    724:2  8 (call-with-prompt _ _ #<procedure default-prompt-handle…>)
In ice-9/eval.scm:
    619:8  7 (_ #(#(#<directory (guile-user) 7fffe9917c80>)))
In ice-9/boot-9.scm:
   2858:4  6 (save-module-excursion _)
  4408:12  5 (_)
In /nix/store/q1f2plxi19fw7pm6gqj01jp6wwy5rv39-readable-1.0.10/bin/unsweeten:
     61:0  4 (_)
In ice-9/boot-9.scm:
  3955:20  3 (process-use-modules _)
   222:17  2 (map1 (((readable kernel))))
  3956:31  1 (_ ((readable kernel)))
   3352:6  0 (resolve-interface (readable kernel) #:select _ #:hide _ …)

ice-9/boot-9.scm:3352:6: In procedure resolve-interface:
no code for module (readable kernel)
```

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

Update documentation.  In particular, document the local
"line continuation" extension as an extension.

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>

- We used AC_PATH... for sbcl and clisp, but they really aren't needed,
    and the full path returned may include spaces (which causes problems).
    Using AC_CHECK... instead, which do not include the full path,
    eliminates those problems.

- This package includes a copy of "asdf.lisp" in case people don't
    already have a version.  You do *NOT* need to use this version, it
    is UNCHANGED from the source, and it is safely put in subdirectory
    "exernal/" to make it unlikely to use by accident.

- Modify Common Lisp implementation of "readable" library so that
    the enable-* routines (such as enable-sweet) are invoked at
    compile time.  This is implemented by turning the enable-* routines
    into macros that use eval-when.  The enable routines are now in a
    separate file, enablers.lisp, so that we can ensure that the macros
    will call routines that have already been compiled.
  - This fixes an error reported by Alexander Dunn on 2014-12-06
    on the readable-discuss mailing list.

- In particular, rename "fact" to "factorial" so the demo
    doesn't interfere with the built-in factorial function.

- This now runs "(setf (readtable-case *readtable*) :invert)",
    which enables nice symbol input and output in lowercase.
    The "invert" mechanism is kind of a hack in Common Lisp, but it
    gets nice results and is completely standard.

- The color-coding for vim gets confused over #\"..., thinking it is
    the start of a string (whups).  Using backquote instead of quote
    works around the issue, without changing the functionality.

- The "appende" function should have (append x y) as the normal case,
    so change to that.  In practice, these have been optimized out,
    so the bug cannot appear in practice, but may as well be clean.