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Issue DEFCONSTANT-VALUE (V2)
- To: Gray@DSG.csc.ti.com
- Subject: Issue DEFCONSTANT-VALUE (V2)
- From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>
- Date: Sun, 9 Oct 88 03:23 EDT
- Cc: CL-Compiler@SAIL.Stanford.edu
- In-reply-to: <2801165093-10211223@Kelvin>
Date: Thu, 6 Oct 88 16:24:53 CDT
From: David N Gray <Gray@DSG.csc.ti.com>
I certainly favor a compile-time evaluation option.
It is implementation dependent whether or not the symbol value is
actually set at compile time or whether COMPILE-FILE temporarily
remembers the value in some other way.
However, I a couple of major problems with this...
It implies that you can't use the variable FOO in either
a macro or an (EVAL-WHEN (COMPILE) ...). That seems unfortunate.
Not only is it sad, but it is sad for no apparent good reason.
There's no efficiency reason that I can think of for not pinning
this down and just saying it will be available at compile time.
Interpreted-only implementations (the usual exception case in
compiler discussions) have no trouble treating this as an assignment.
And there's no other reason I can think of why you couldn't want
For reasons both of flexible coding style and principle of least
surprise in portability, I would prefer that we just require this
to assign the variable at compile time (for at least the duration
of the file -- if someone needs it beyond the end of the file, they
can load the file).