README

All my personnal unix commands written in Common Lisp are gathered here.

Originally, they used clisp to as #! interpreter.

However, since clisp development is slower than that of some host systems,
this causes some problems on newest systems.

Unfortunately, switching to cl-launch proves unsatisfactory.
The main problems of cl-launch and #!/usr/local/bin/cl are that:

1- they don't maintain the "script" aspect of the lisp code. Namely,
   by insisting on compiling and loading the code before executing, we
   cannot have forms that depend on the execution of previous forms.
   In the case of scripts, this is particularly problematic, when we
   have to inspect the environment and adapt to it, at run-time.

2- the compilation and loading is performed on a copy of the source
   script, therefore we cannot use *load-pathname* or
   *compile-file-pathname* as a basis for script resources or other.

3- they rely on quicklisp, which introduces some brittleness (and a
   dependency on the user installation!).


In particular, once we allow quicklisp in, there's no real advantage
to maintain the notion of script and the #!-interpreter aspect and
lightweightness.

At the cost of some code duplication, loading and running the previous
scripts could be fast and free of external dependencies other than the
#!-interpreter.  Once we allow or require quicklisp and loading
libraries with it, there's no point in further maintaining the script
illusion.

In consequence, the new model is to load in a single executable lisp
image, all the "small programs" that are the scripts, and to dispatch
according to the invocation program name.

This transformations will have some advantages and some inconvenients:

- we will be able to eliminate code duplications, which should be good
  for maintainability,

- since all the code is already loaded and compiled in the same
  executable image in the cache, startup time and run-time should be
  improved.

- we must now avoid load-time execution (eg. defvar/defparameter
  initialization forms or other toplevel forms), and global state
  collisions (help or options will need some refactoring work).

- scripting/command infrastructure will benefit all the commands.

- uiop:run-program is insufficient (no :stream I/O, no pipe), so some
  works will be needed to revert functionality.  (I'll have to revive
  my portable implementation of run-program).

--
__Pascal Bourguignon__