<Mirko.Vukovic@gmail.com> wrote:
+---------------
| I would like to define a package that defines values of physics
| constants.  I would than import some of these constants into my
| working package.  But I would like to rename the constants.
| 
| For example, suppose I have a constant defined as *speed-of-light* in
| the :physics-constants package.  But that is long and overly
| descriptive, and in my working package I would like to use "c".
| 
| Now I guess I could write a macro wrapper to use-package when it comes
| to importing variables from my physics-constants package.  (Or maybe
| package is overkill for my purpose.  I could use some kind of hash and
| rename on the fly.)
+---------------

Ouch! That sounds way too heavyweight for simple renaming of a few
constants. What about just using DEFINE-SYMBOL-MACRO? E.g.:

    (define-symbol-macro +c+ physics-constants:+speed-of-light+)

Note: Just as *...* is conventionally used for special variables
(DEFVAR/DEFPARAMETER), +...+ is the CL convention for constants
(DEFCONSTANT). Though calling it simply "C" probably isn't an issue
in this case, since names defined with DEFINE-SYMBOL-MACRO *can* be
lexically rebound with LET or SYMBOL-MACROLET. [Names defined with
DEFCONSTANT can't.]


-Rob

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