[Ecls-list] (si:package-lock :cl t)

[Matthew Mondor]

Hello,

Since in Common Lisp, using the :USE option of DEFPACKAGE causes
dynamic binding of exported symbols of the used package into the new
package, DEFUN is able to override CL functions.  After checking out
the ECL code, I found out that I can use (SI:PACKAGE-LOCK :CL T) to
lock the COMMON-LISP package and cause an error to be signaled when
trying to override a CL symbol this way.

I'm glad that I can use this feature to prevent inadvertent bugs in my
software (I don't yet remember all CL symbols :).  But some
implementations (i.e. SBCL) by default lock the CL package.  So I
wondered: Is there a technical reason why this is not the default for
ECL?  Or known software which breaks with this?

Thanks,
-- 
Matt