Behavior of joining paths starting with "/" is unnatural #12

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1. kylef commented on Mar 22, 2016

   

   kylef

   on Mar 22, 2016

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   I disagree that this is unnatural, it's actually consistent with many other languages and join implementations. It's exactly how I'd expect it to work.

   Could you perhaps explain your use-case a bit more so we can try and find a different solution? Why would your right hand have a slash in it already?

   A cross-platform solution would look more like:

   let root = Path(Path.separator)
   let usrBin = (root + "usr") + "bin"
   let swift = usrBin + "swift"

   If you're supporting multiple platforms, you cannot rely on the fact that / is the separator, it could be something else such as \. The whole point around this API is to join paths without hard-coding "/" as a string everywhere.

   Python

   https://docs.python.org/3.5/library/os.path.html#os.path.join

   If a component is an absolute path, all previous components are thrown away and joining continues from the absolute path component.

   >>> from os import path
   >>> path.join("/usr/local", "/swift")
   '/swift'

   Ruby

   Can't find a statement in the documentation, but you can see the behaviour is the same:

   > Pathname.new('/usr/bin').join('/swift')
   => #<Pathname:/swift>

   Cocoa (NSURL)

   Again, I can't find a part of the documentation, but here is the behaviour.

   NSURL(fileURLWithPath: "/swift", relativeToURL:NSURL(fileURLWithPath: "/usr/bin"))
   // --> file:///swift

   👍React with 👍1Reacted by Arthur Mironenko
2. kenjitayama commented on Mar 22, 2016

   

   kenjitayama

   on Mar 22, 2016

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   Thank you for explaining in detail.
   I see you're pretty right that it's consistent and natural.

   I had one counter example in mind.

   let basePath = NSURL(fileURLWithPath: "/base/path")
   let path = basePath.URLByAppendingPathComponent("/some/path")
   // --> file:///base/path/some/path
   

   Anyways, my use case is…
   I have some generated swift code that I can't control, and has let path = "/some/path" in it.
   And I need to concatinate it to a let basePath = Path("/base/path").
   With the current implementation, I need to String(path.characters.dropFirst()) before concatination.
   These paths are acutually part of a URL, so I don't need to worry about path separators.

   Would you say this is not a use case for PathKit, or am I missing a better approach using PathKit?

   Thanks in advance for advice.
3. kenjitayama commented on Mar 24, 2016

   

   kenjitayama

   on Mar 24, 2016

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   I found this behaviour in Ruby.

   base_path = "/base/path"
   path = "/some/path"
   result_path = File.join(base_path, path) // => /base/path/some/path
   

   I think, at least there are some demands for this style of concatination.
4. rbukovansky commented on Oct 11, 2016

   

   rbukovansky

   on Oct 11, 2016

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   Boy, I don't want to see debate about this when Apple or somebody brings Swift to Windows... (slash and backslash works both, drives' letters etc.)