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Subject: Re: [boost] [Filesystem] v3 path separator changes
From: Alexander Lamaison (awl03_at_[hidden])
Date: 2013-03-24 15:12:56

Yakov Galka <ybungalobill_at_[hidden]> writes:

> On Sun, Mar 24, 2013 at 8:03 PM, Alexander Lamaison <awl03_at_[hidden]>wrote:
>> Rob Stewart <robertstewart_at_[hidden]> writes:
>> [...]
>> >>
>> >> In that case I'd expect it to output "\a\b\c". I can't think of a
>> >> reason why mixed slashes would ever be the right answer. It's the
>> >> worst of both worlds.
>> >
>> > You're expecting this line
>> >
>> > path p("/a/b");
>> >
>> > to parse your string into "a" / "b" when it merely stores the string
>> > as you gave it.
>> That's not true. It does parse the string and recognises "a" and "b" as
>> separate segments of the path. If it didn't, iteration would return
>> "a/b" followed by "c". I wrote a small program (included at the end) to
>> prove this. Here is the output:
> Based on previous conversations with Beman, I think that what Rob Stewart
> means, and correct me if I'm wrong, is that one "feature" of the library is
> the assertion path(str).string() == str.

It does now. It didn't used to and I'm struggling to see what the
benefit of the change was. After all, if all you want is the original
string why would you even use the path class.

> In other words: boost::path is a very dump strong typedef for a string that
> magically does encoding conversions and has some syntactic operations
> defined, like operator / that adds a *slash*. (...or a *backslash* on other
> platforms...)
> It seems that the designer of the library does not like the idea that path
> be a higher level platform independent abstraction of paths. As I'd say
> many times I see little use in the current path class, and I personally use
> UTF-8 std::strings everywhere with suitably defined operations. What annoys
> me is that Boost.filesystem has a fairly good multiplatform implementation
> of filesystem operative functions, but which depends on this dumb path
> class.

I wouldn't write off the path class entirely. It was what first got me
in to Boost all those years ago! But it could be better and some of the
recent changes don't make sense to me.


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