Old python version support

[JunCEEE]

Good job. I can install the package and run the tutorial quickly in the required environment.

However, many of the XFEL environments were deployed with an older python (e.g. 3.7). Would it be possible to make it compatible with older python versions (e.g. from 3.6)?

The error I got in python3.8:

Traceback (most recent call last):
  File "../lib/python3.8/site-packages/beartype/peps/_pep563.py", line 591, in resolve_pep563
    func_hints_resolved[pith_name] = eval(
  File "<string>", line 1, in <module>
TypeError: 'type' object is not subscriptable

[szsdk]

In production environments, the system's dependencies are often quite outdated. However, in development, we often wish to utilize new language features to help us build a more robust software. This can be a challenging situation, where we need to find a balance between utilizing new technologies and ensuring compatibility with older systems. Fortunately, this library is relatively simple, and we can easily remove some of the new language features to make it compatible with lower versions of Python.

Here is a short script which gets rid of all type hints and numpy.typing.

for f in $(find emcfile/ -name  "*.py");
do
    echo $f
    strip-hints $f --inplace --to-empty 
    sed -i -e '/^from typing.*/a from typing import List' \
        -e 's/\/,//g' \
        -e 's/import numpy.typing.*//g' \
        -e 's/npt.NDArray/List/g' $f
done

To run this script, a python package is needed.

[JunCEEE]

I created a script based on your suggestion: https://github.com/JunCEEE/emcfile/blob/fix_py3.6/strip_hints.sh. And created a branch for python 3.6: https://github.com/JunCEEE/emcfile/tree/fix_py3.6 However, I got stuck in this error:

Traceback (most recent call last):
  File "tutorial_00.py", line 8, in <module>
    import emcfile as ef
  File "/emcfile/__init__.py", line 26, in <module>
    from ._patterns import PATTERNS_HEADER, patterns, patterns_header
  File "emcfile/_patterns.py", line 28, in <module>
    tuple[int, int],
TypeError: 'type' object is not subscriptable

It seems that this syntax tuple[int, int] is only supported after python 3.9 according to this post. Do you have any suggestion to fix it?

[szsdk]

@JunCEEE You should use the lastest version. It is already fixed.