m-list: A MATLAB-like Matrix notation for Python, inpired by f-string

m_list.py

"""
File: mlist.py
Author: Marco Aguiar
Github: https://github.com/yourname

MList: A MATLAB-like Matrix notation for Python inpired by f-string 

Are you tired of the unergonomic notation for Python?
Are you tired of thinking: "Does the inner list represents a column or a row?"?
If none of the above, but still you want see some Python trickery, this is for you!

How to use?
- use the syntax m[...], to create a numpy.matrix
- Use `,` to split the elements of the row
- Use `:` to split the rows (equivalent to ; in MATLAB)
- There is only one limitation, you can't make column vectors with more than 3 elements.
But you can make a row vector and transpose it!

Example

>>> from m_list import m
...
... a = m[1]
... b = m[1:2]
... c = m[1:
...       2:
...       3]
... d = (m[1,2,3,4,5])
... Q = m[1, 2:
...       3,-4:
...       5, 6]
... H = m[0.1, 0:
...       0,  -3.4]
... print(repr(a), repr(b), repr(c), repr(d), repr(Q), repr(H),sep="\n")
matrix([[1]])
matrix([[1],
        [2]])
matrix([[1],
        [2],
        [3]])
matrix([[1, 2, 3, 4, 5]])
matrix([[ 1,  2],
        [ 3, -4],
        [ 5,  6]])
matrix([[ 0.1,  0. ],
        [ 0. , -3.4]])
"""


from typing import Iterable, List, Tuple, Union
import numpy


class m:
    def __class_getitem__(
        cls, items: Union[slice, Tuple[Union[float, slice], ...]]
    ) -> numpy.ndarray:
        rows: List[List[float]] = [[]]

        # eg: m[1:2:3]
        if isinstance(items, slice):
            cls._handle_slice(rows, items)
            if items.step is not None:
                rows.append([items.step])

        # eg: m[1,2:3,4]
        elif isinstance(items, Iterable):
            for item in items:
                if not isinstance(item, slice):
                    rows[-1].append(item)
                    continue
                cls._handle_slice(rows, item)
        else:
            rows[-1].append(items)

        return numpy.matrix(rows)

    @staticmethod
    def _handle_slice(rows: List[List[float]], item: slice):
        rows[-1].append(item.start)
        rows.append([item.stop])


if __name__ == "__main__":
    a = m[1]
    b = m[1:2]
    c = m[1:2:3]
    d = m[1, 2, 3, 4, 5]

    Q = m[1, 2:3, -4:5, 6]

    H = m[0.1, 0:0, -3.4]

    print(repr(a), repr(b), repr(c), repr(d), repr(Q), repr(H), sep="\n")