library support request: attrs

One of the major reasons that I want to eventually have a python-in-the-browser option is so that I can easily share complex data structures between the frontend and the backend.

Problem: I currently define all my complex data structures with https://github.com/python-attrs/attrs, and brython cannot import this code 😃.

I think this is a great library to try to get Brython to run unmodified, because it is doing lots of standard Python and platform detection at startup time, and using various standard library modules; yet, it does no I/O, requires no other libraries; it’s purely for defining data structures, so it should work just as well in Brython as in CPython.

Just a few things I hit while trying to import it:

• functools.partial()
• sys.version_info
• platform.python_implementation()

None of these things seem hard to implement individually but there are probably a dozen of them before it will import.

Thanks again for brython!

[PierreQuentel]

In branch “rewrite_classes”, this code now works correctly:

import attr

@attr.s
class SomeClass(object):
    a_number = attr.ib(default=42)
    list_of_numbers = attr.ib(default=attr.Factory(list))

    def hard_math(self, another_number):
        return self.a_number + sum(self.list_of_numbers) * another_number


sc = SomeClass(1, [1, 2, 3])
print(SomeClass(a_number=1, list_of_numbers=[1, 2, 3]))

assert sc.hard_math(3) == 19
assert sc == SomeClass(1, [1, 2, 3])
assert sc != SomeClass(2, [3, 2, 1])

[glyph]

It’s possible that you didn’t include brython_stdlib.js in your script (if I remove it I also have an error message related to a missing future module)

That is indeed the problem; when I add brython_stdlib.js, attrs works fine!

@hynek - time to add brython to attrs’ CI? 😃