[r6rs-discuss] R5.95 questions

From: Thomas Lord <lord>
Date: Wed, 27 Jun 2007 01:53:53 -0700

Michael Sperber wrote:
> So, here's a question for the native speakers: I want to write something
> like
>
> "Implementations must check these restrictions only to the extent that
> ..."
>
> Meaning that a minimal requirement follows, but implementations are free
> to do more checking. Does the sentence say what I mean, or does it say
> that they must not check more than what follows? If the latter, how do
> I say what I want to say using "must"?
>
>


Cowan has it about right. In this case, the word "only" is doing you
no good. "Must...only" means "(i.e., must not do more than)" but
"must..." alone just means "must".

It makes more sense if you say:

  "Implementations must check these restrictions to the extent that..."

There is no "only" about it in this formal context. The implementations
must do "something" and in this case that "something" is described
by a a phrase that begins "check [certain] restrictions to the extent
that...."

All that said, colloquially, nobody would misunderstand your "must...only".
Colloquially, "only" just emphasizes some meta-point that the requirement
is here being weakened in some way -- but formally, we don't recognize
that usage.

Formally, for example, if Congress put "must...only" in a law and the
Supreme Court were reading it, absent overwhelming reason to the contrary,
the court would read "must do the following and must not do anything beyond
that".

-t
Received on Wed Jun 27 2007 - 04:53:53 UTC