Next: , Up: Declarations   [Contents][Index]

4.2.1 Standard Names

Normally, all files have a line

(declare (usual-integrations))

near their beginning, which tells the compiler that free variables whose names are defined in system-global-environment will not be shadowed by other definitions when the program is loaded. If you redefine some global name in your code, for example car, cdr, and cons, you should indicate it in the declaration:

(declare (usual-integrations car cdr cons))

You can obtain an alphabetically-sorted list of the names that the usual-integrations declaration affects by evaluating the following expression:

(eval '(sort (append usual-integrations/constant-names
             (lambda (x y)
               (string<=? (symbol->string x)
                          (symbol->string y))))
      (->environment '(scode-optimizer)))