Styles for Boot Codes
---------------------

  The core of the OpenAxiom system is mostly written in Boot.  A long
time ago, Boot was essentially a Lisp DSL with a much more palatable
syntax geared specifically toward  writing readable codes.  As such it
tended to have lots of Lispism in it.

  There days, Boot is no longer `just a syntactic sugar over Lisp',
even when we essentially translate to Lisp.  Boot is a
programming language in of its own.  In fact, we would like to remove
Lispism from Boot codes.  The `rules' below are suggestions (or
guidelines) for writing `good Boot codes'.


* In general, you should precede your functions definitions with
  ++ comments that describes the semantics of the functions, its
  pre- and post-conditions.

* Use -- comments only for non-descriptive remarks, such as in
  function body.

* Always precede your functions definitions with type declarations.
  Exception to this rule should be rare and documented.


* Don't use Lisp functions directly in Boot codes, except where
  they are for interfacing with Lisp.

   Example: 

      -- GOOD --
      first form in '(Mapping Record) => -- ...
      form.first := '%LET

      -- BAD --
      CAR form in '(Mapping Record) => -- ...
      RPLACA(form,'%LET)

* Don't use `null' to test for Boolean values, use `not'

   Example:

      -- GOOD --
      not $monitorNewworld => ...

      -- BAD --
      null $monitorNewworld => ...

* Use idiomatic Boot constructs

   Example:
     -- GOOD --
     vars := [var,:vars]

     -- BAD --
     vars := CONS(var,vars)