Traceback (most recent call last):


 "<stdin>", line 1, in <module>


 "/Users/Julian/.local/share/virtualenvs/dev/site-packages/pyrsistent/_pmap.py", line 419, in pmap

return _turbo_mapping(initial, pre_size)


 "/Users/Julian/.local/share/virtualenvs/dev/site-packages/pyrsistent/_pmap.py", line 381, in _turbo_mapping

size = pre_size or (2 * len(initial)) or 8
TypeError: 'generator' has no length

Traceback (most recent call last):


 "/usr/local/bin/meson", line 11, in <module>

load_entry_point('meson==0.53.0', 'console_scripts', 'meson')()


 "/usr/local/lib/python3.5/dist-packages/pkg_resources/__init__.py", line 489, in load_entry_point

return get_distribution(dist).load_entry_point(group, name)


 "/usr/local/lib/python3.5/dist-packages/pkg_resources/__init__.py", line 2852, in load_entry_point

return ep.load()


 "/usr/local/lib/python3.5/dist-packages/pkg_resources/__init__.py", line 2443, in load

return self.resolve()


 "/usr/local/lib/python3.5/dist-packages/pkg_resources/__init__.py", line 2449, in resolve

module = __import__(self.module_name, fromlist=['__name__'], level=0)


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/mesonmain.py", line 25, in <module>

from . import mconf, mdist, minit, minstall, mintro, msetup, mtest, rewriter, msubprojects, munstable_coredata


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/mconf.py", line 16, in <module>

from . import coredata, environment, mesonlib, build, mintro, mlog


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/environment.py", line 32, in <module>

from . import compilers


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/compilers/__init__.py", line 102, in <module>

from .compilers import (


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/compilers/compilers.py", line 389, in <module>

class CompilerArgs(typing.MutableSequence[str]):


 "/usr/local/lib/python3.5/dist-packages/mesonbuild/compilers/compilers.py", line 658, in CompilerArgs

def __eq__(self, other: typing.Any) -> typing.Union[bool, 'NotImplemented']:

"Forward references must evaluate to types.")


 "/usr/lib/python3.5/typing.py", line 312, in _type_check

raise TypeError(msg + " Got %.100r." % (arg,))
TypeError: Forward references must evaluate to types. Got NotImplemented.
