Re: byte compiling defcustom

[Richard Stallman]

    (defvar foo     (if (featurep 'xemacs) 'bar 'baz) "doc")
    (defcustom foo1 (if (featurep 'xemacs) 'bar 'baz) "doc")


    Are compiled to:

    (defvar foo 'baz (#$ . 543))
    (custom-declare-variable 'foo1 '(if (featurep 'xemacs) 'bar 'baz) '(#$ . 
581))

The initial value expression for defcustom is saved and gets
recalculated later in some cases.  So it cannot in general be
optimized.

This particular simplification could be done even in defcustom, since
(featurep 'xemacs) is effectively a constant.  But why bother
to implement that optimization?  It works fine as it is now.