At 03:16 PM 11/23/2004, Rich Johnson wrote:
Yup. This is getting further into hypothetical design than is probably appropriate, but....assuming the FS provides an is_name_equivalent() convenience function (which I think it should):
A monolithic 'is_name_equivalent()' function that sets up and tears down a regex each time it's invoked would have performance issues when used in the context of the globber.
A reusable 'name_comparator' object(functor) supplied by the FS layer could be instantiated once as part of the glob_predicate.
Of course this raises the issue of what happens when you glob across a FS boundary(mount points and links)--must the name_comparator change accordingly?
On Windows, it is not possible to tell if two names (or paths) are equivalent just by looking at the name (or path). The question can only be answered by inspecting the current state of the filesystem. For example, if a directory contains both files "A" and "a", then these two names are not equivalent. But if the directory only contains a file named "A", then "a" is equivalent in that directory at the current time. Since you can't determine equivalence, if neither exist then the equivalent() function throws in that case. --Beman