On Oct 7, 2010, at 12:54 AM, Oliver Kiddle wrote: > "Jeffrey B. Green" wrote: >> My assumption is that two forms said to be equivalent imply the results >> of the forms are identical, they can be substituted for each other. >> Otherwise, they not not equivalent, just similar. What is your >> definition of equivalent? > > But the man page doesn't just say "equivalent", it says "equivalent (as > far as the above execution of cmd is concerned". And the whole > paragraph is clearly just talking about the environment passed to an > executed program. The evaluation of a command's arguments is all done > as a separate thing. > > If you can think of some better wording which doesn't clutter it up and > detract from the main point that is being made then I'll put it forward > to upstream.
The issue is what is the context of "the" execution, or what are the exceptions for the rule stated. It is difficult to state the context unambiguously and briefly. The fact is that args is evaluated in the old environment and cmd is evaluated in the new one, in that order. Stating that or something similar basically says unambiguously what is happening. (Sorry for using functional language terms, they seem appropriate here.) So how to present something that upstream can work with, I'm assuming upstream means the Bell Labs people. What I would say to them is that the phrasing is misleading. (A fine tuning of the phrase is probably the best approach here since I assume they are a bit attached to it.) To state that two forms are equivalent is a fairly strong statement. Modifying that with conditions must then handle any ambiguities that arise in a clear way, especially for shell users as opposed to shell developers. To be picky, the phrase "as far as" doesn't work. A better one is "only as far as", however even that leaves room for misunderstanding. I would state it as "only as far as the execution of cmd (and not args) is concerned except for ...". I believe that phrase is what I would suggest. I hope that helps, -jeff -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
