Re: System.FilePath propsal (Was: Cabal feedback notes)

At 06:52 28/10/04 -0700, Krasimir Angelov wrote:

--- Graham Klyne wrote:

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2. How does path joining work in this case:

joinPaths C:/root/path/file.ext altPath/file2.ext2

i.e. is "file.ext" discarded?

No. You will get:

C:/root/path/file.ext/altPath/file2.ext2

Hmmm. I can't claim it's wrong, but I'm uneasy about that. It is, for example, different from the way that URI path joining works.

What do you expect to get? file.ext is a valid directory name.

Indeed it is. This is, I believe, an ambiguity with the way Unix-like-systems present directory and file names, which cannot be disambiguated without actually consulting the live file system. Windows has a similar issue. The URI path-joining algorithm would drop the final "filename" element 'file.ext' (not being terminated by '/'), and give: C:/root/path/altPath/file2.ext2

By the way

joinPaths "c:/dir1/file.ext" "c:/dir2" == "c:/dir2"

because the second path is absolute.

Good. That's as I'd expect.

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What about:

joinPaths C:/root/path/ altPath/file2.ext2

does this give: C:/root/path/altPath/file2.ext2 or C:/root/path//altPath/file2.ext2

?

The first one. "//" is equal to "/", isn't it?

Is it? Is it definitely prohibited to have a zero length path segment. What is the correct interpretation of this: C:/root/path//../altPath/file2.ext2 ? (I'm not saying you're wrong, just that the answer isn't entirely clear-cut.) ... BTW, whatever the final answer, I think it would be a great idea to have a unit test module (preferably using HUnit) with all these as test cases. If only to definitively settle questions from awkard people like me. #g ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact