of::filesystem, ideas

[dimitre]

Some ideas

• of::filesystem::path can be used in more places substituting strings when dealing with paths and filenames
  both in OF and PG.
• Boost can be updated so we can use filesystem v4 which is more similar to std::filesystem
• we can think about deprecating some old functions as addTrailingSlash and others

--- Past Stuff
Complete PR here #7110

I was wondering if instead of trying to insert filesystem namespace inside of std, how about we just use the

in ofConstants.h, one of this depending on defines

namespace filesystem = std::__fs::filesystem;
namespace filesystem = std::fs::filesystem;
namespace filesystem = boost::filesystem;
namespace filesystem = std::experimental::filesystem;

in ofFileUtils.h for example

bool open(const filesystem::path & path, Mode mode=ReadOnly, bool binary=true);

of course I don't understand about std::filesystem so it can be a very bad idea, but would like to know your opinion

[dimitre]

DeadSix27/waifu2x-converter-cpp#251 (comment)

[ofTheo]

Hey @dimitre
That could definitely be a simpler / cleaner approach and similar to how other projects handle it.

Would be up for trying this as the current approach has some edge cases which cause ambiguous errors.

[dimitre]

Nice, I can make a PR soon for testing. Any suggestions of namespace? we can try as the example above?

[dimitre]

Other suggestion : probabaly with addons breaking potential, but I think it worths:
there are a lot of functions that manipulate paths, ex: ofToDataPath which converts back and forth from fs::path to string
My suggestion is we migrate to fs::path when possible.

I had to modify my own addons to use ofToDataPath().string()

[dimitre]

First draft
https://github.com/dimitre/openFrameworks/tree/lite

[ofTheo]

The only downside I can see to this approach:

bool open(const filesystem::path & path, Mode mode=ReadOnly, bool binary=true);

is if someone puts using namespace std; then there might be some ambiguous errors if they have forced the boost::filesystem to be filesystem. as filesystem could refer either to the boost one or std::filesystem

Alternative:

namespace fs = std::filesystem;

with this usage

bool open(const fs::path & path, Mode mode=ReadOnly, bool binary=true);

would be safer but it also feels much less clear.

bool open(const ofFileSystem::path & path, Mode mode=ReadOnly, bool binary=true);

could be an option but that sort of hides what it is. I guess the upside would be that it is discoverable in the OF code completion - but again might be confusing?

One more that might be cleaner and lean into the of namespace we have been talking about:

bool open(const of::filesystem::path & path, Mode mode=ReadOnly, bool binary=true);

Curious what people think.

[2bbb]

I agree with bool open(const of::filesystem::path & path, Mode mode=ReadOnly, bool binary=true);.

[dimitre]

Yeah of::filesystem is nice. I can make some changes in the fork.

[dimitre]

About this same subject, is this the right time to remove boost::filesystem ?

[dimitre]

PR is now complete and on master, this is great, and it opens new possibilities of rethinking (simplifying, improving) pieces of OF like filePath object and projectGenerator.
There are some discussion and decisions made on the PR so I'm linking here as a reference #7110

and I'll link this other one as some future ideas arised there too - #7368

[dimitre]

Other PR to have in mind - #7361

[dimitre]

Lots of things were decided and merged after this discussion, happy to see filesystem in more places. projectGenerator now uses it extensively.
I'm thinking about this next steps, in this specific order:

• More of::filesystem : streamline path inside core #7383 (comment)
• [Windows] wchar_t for executable path  #7494
• [Windows] load image with filenames other than english #7435

I'll be buying a second hand windows box just to test the windows related PRs and projectGenerator