Slist
This is a drop in replacement for the built-in mutable python list
But with more post-fixed methods for chaining in a typesafe manner!!
Leverage the latest pyright features to spot errors during coding.
All these methods return a new list. They do not mutate the original list.
Not able to convince your colleagues to use immutable functional data structures? I understand.
This library lets you still have the benefits of typesafe chaining methods while letting your colleagues have their mutable lists!
pip install slist
- Documentation: https://thejaminator.github.io/slist/
Quick Start
Easily spot errors when you call the wrong methods on your sequence with mypy.
from slist import Slist
many_strings = Slist(["Lucy, Damion, Jon"]) # Slist[str]
many_strings.sum() # Mypy errors with 'Invalid self argument'. You can't sum a sequence of strings!
many_nums = Slist([1, 1.2])
assert many_nums.sum() == 2.2 # ok!
class CannotSortMe:
def __init__(self, value: int):
self.value: int = value
stuff = Slist([CannotSortMe(value=1), CannotSortMe(value=1)])
stuff.sort_by(lambda x: x) # Mypy errors with 'Cannot be "CannotSortMe"'. There isn't a way to sort by the class itself
stuff.sort_by(lambda x: x.value) # ok! You can sort by the value
Slist([{"i am a dict": "value"}]).distinct_by(
lambda x: x
) # Mypy errors with 'Cannot be Dict[str, str]. You can't hash a dict itself
Slist provides methods to easily flatten and infer the types of your data.
from slist import Slist, List
from typing import Optional
test_optional: Slist[Optional[int]] = Slist([-1, 0, 1]).map(
lambda x: x if x >= 0 else None
)
# Mypy infers slist[int] correctly
test_flattened: Slist[int] = test_optional.flatten_option()
test_nested: Slist[List[str]] = Slist([["bob"], ["dylan", "chan"]])
# Mypy infers slist[str] correctly
test_flattened_str: Slist[str] = test_nested.flatten_list()
There are plenty more methods to explore!
from slist import Slist
result = (
Slist([1, 2, 3])
.repeat_until_size_or_raise(20)
.grouped(2)
.map(lambda inner_list: inner_list[0] + inner_list[1] if inner_list.length == 2 else inner_list[0])
.flatten_option()
.distinct_by(lambda x: x)
.map(str)
.reversed()
.mk_string(sep=",")
)
assert result == "5,4,3"
1 maintainer
Metadata
1 maintainer
Release files for slist 0.3.17
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| File | Size | Uploaded | Provenance | |
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|---|---|---|---|---|
| slist-0.3.17-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 38.1 kB
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