Metadata-Version: 2.1
Name: iterpy
Version: 1.11.1
Summary: iterpy
Author-email: Martin Bernstorff <martinbernstorff@gmail.com>
License: MIT License
        
        Copyright (c) Martin Bernstorff
        
        For some subsections, closely inspired by Flupy and hence probably Copyright (c) Oliver Rice.
        
        Permission is hereby granted, free of charge, to any person obtaining a copy
        of this software and associated documentation files (the "Software"), to deal
        in the Software without restriction, including without limitation the rights
        to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
        copies of the Software, and to permit persons to whom the Software is
        furnished to do so, subject to the following conditions:
        
        The above copyright notice and this permission notice shall be included in all
        copies or substantial portions of the Software.
        
        THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
        IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
        FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
        AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
        LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
        OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
        SOFTWARE.
        
Project-URL: homepage, https://github.com/MartinBernstorff/iterpy
Project-URL: repository, https://github.com/MartinBernstorff/iterpy
Project-URL: documentation, https://MartinBernstorff.github.io/iterpy/
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: 3.11
Classifier: Programming Language :: Python :: 3.12
Requires-Python: >=3.9
Description-Content-Type: text/markdown
License-File: LICENSE

# iterpy

[![Open in Dev Container](https://img.shields.io/static/v1?label=Dev%20Containers&message=Open&color=blue&logo=visualstudiocode)][dev container]
[![PyPI](https://img.shields.io/pypi/v/iterpy.svg)][pypi status]
[![Python Version](https://img.shields.io/pypi/pyversions/iterpy)][pypi status]
[![Roadmap](https://img.shields.io/badge/Projects-Roadmap-green)][roadmap]

[pypi status]: https://pypi.org/project/iterpy/
[dev container]: https://vscode.dev/redirect?url=vscode://ms-vscode-remote.remote-containers/cloneInVolume?url=https://github.com/MartinBernstorff/iterpy/
[roadmap]: https://github.com/users/MartinBernstorff/projects/3/views/1?groupedBy%5BcolumnId%5D=70727793&sliceBy%5BcolumnId%5D=Status&filterQuery=-status%3ADone

<!-- start short-description -->

Python has implemented `map`, `filter` etc. as functions, rather than methods on a sequence. Since it does not contain a pipe operator, this makes the result harder to read. iterpy exists to change that.

You get this 🔥:

```python
from iterpy import Iter

result = Iter([1,2,3]).map(multiply_by_2).filter(is_even)
```

Instead of this:

```python
sequence = [1,2,3]
multiplied = [multiply_by_2(x) for x in sequence]
result = [x for x in multiplied if is_even(x)]
```

Or this:

```python
result = filter(is_even, map(multiply_by_2, [1,2,3]))
```

<!-- end short-description -->

## Install

```bash
uv add iterpy
```

## Usage

```python
from iterpy import Iter

result = (Iter([1, 2])
            .filter(lambda x: x % 2 == 0)
            .map(lambda x: x * 2)
            .to_list()
)
assert result == [4]
```

### Lazy vs eager evaluation

Inspired by Polars, iterpy supports eager evaluation for easier debugging using `Arr`, and lazy evaluation for better performance using `Iter`. To access eager evaluation:

```python
from iterpy import Arr

result = Arr([1, 2, 3]).map(lambda x: x * 2).to_list()
assert result == [2, 4, 6]
```

`Arr` acts like a Python `list`, so you can pass it around anywhere flexibly!

To access lazy evaluation, just rename `Arr` to `Iter`:

```python
from iterpy import Iter

result = Iter([1, 2, 3]).map(lambda x: x * 2).to_list()
assert result == [2, 4, 6]
```

## Prior art

iterpy stands on the shoulders of Scala, Rust etc.

Other Python projects have had similar ideas:

- [PyFunctional](https://github.com/EntilZha/PyFunctional) has existed for 7+ years with a comprehensive feature set. It is performant, with built-in lineage and caching. Unfortunately, this makes typing [non-trivial, with a 4+ year ongoing effort to add types](https://github.com/EntilZha/PyFunctional/issues/118).
- [flupy](https://github.com/olirice/flupy) is highly similar, well typed, and mature. I had some issues with `.flatten()` not being type-hinted correctly, but but your mileage may vary.
- Your library here? Feel free to make an issue if you have a good alternative!

## Contributing

### Setup

1. We use [`uv`](https://docs.astral.sh/uv/) for environment management. Once it is installed, setup the dev environment using `make dev`.

Or, use the devcontainer.

1. Install [Orbstack](https://orbstack.dev/) or Docker Desktop. Make sure to complete the full install process before continuing.
1. If not installed, install VSCode
1. Press this [link](https://vscode.dev/redirect?url=vscode://ms-vscode-remote.remote-containers/cloneInVolume?url=https://github.com/MartinBernstorff/iterpy/)

### Changes

2. Make your changes

3. See the makefile for tests, linting, and formatting.

### Conventions

- Make it work: Concise syntax borrowed from Scala, Rust etc.
- Make it right: Fully typed, no exceptions
- Make it fast:
  - Concurrency through `.pmap`
  - (Future): Caching
  - (Future): Refactor operations to use generators
- Keep it simple: No dependencies

### API design

As a heuristic, we follow the APIs of:

- Rust's [std::iter](https://doc.rust-lang.org/stable/std/iter/)
- Rust's [itertools](https://docs.rs/itertools/latest/itertools/index.html)

In cases where this conflicts with typical python implementations, the API should be as predictable as possible for Python users.

## 💬 Where to ask questions

| Type                            |                        |
| ------------------------------- | ---------------------- |
| 🚨 **Bug Reports**              | [GitHub Issue Tracker] |
| 🎁 **Feature Requests & Ideas** | [GitHub Issue Tracker] |
| 👩‍💻 **Usage Questions**          | [GitHub Discussions]   |
| 🗯 **General Discussion**        | [GitHub Discussions]   |

[github issue tracker]: https://github.com/MartinBernstorff/iterpy/issues
[github discussions]: https://github.com/MartinBernstorff/iterpy/discussions
