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

Krasimir, Thanks for your work on this, and your responses... At 13:05 27/10/04 -0700, Krasimir Angelov wrote:

--- Graham Klyne wrote:

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1. How are multiple extensions handled? (e.g. foo.tar.gz) I think this is catered for, with the final extension being picked off.

splitFileExt always return the last extension.

Sounds good to me.

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

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3. What is the purpose of commonInit?

commonInit is renamed to commonParent in the last version. It returns the largest path that is common in all paths in the list.

Ah, I see.

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Also, a very small point: I forgot that FilePath is defined in the prelude... maybe a comment to this effect on the module export list?

I will add FilePath to the export list (Simon's suggestion).

With a comment that it is defined in the Prelude?

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I'm rather taken by the approach that Peter Simons suggests [1] (abstracting the path composition), but I suspect there are more details to be worked out there. It also makes my earlier suggestion [2] of using a URI-based representation as a common abstraction seem slightly less radical. I also note Simon's comments on this (don't do it yet_) are persuasive. I'll reserve my campaign to unify filenames and URIs for the "ultimate" FilePath abstraction ;-)

It could be great to have filePathToURI and uriToFilePath functions in Network.URI. There we can also have URI manipulation functions but this doesn't mean that we don't need have System.FilePath in addition.

I've been toying with ideas for creating scheme-specific URI functions in sub-modules, e.g. Network.URI.http Network.URI.file etc. When the IETF decides what to do about the revised file: URI specification, I might give this a try, lifting some code I wrote for XML processing. #g ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact