Caution

THIS LIBRARY IS CURRENTLY PRE-RELEASE

pkl-python is currently major version v0, and breaking changes will happen between versions.

pkl-python - Pkl Bindings for Python

Python binding for Apple's Pkl language.

Getting Started

Installation

pip install pkl-python

Basic Usage

Here's how you can start using pkl-python to load a PKL module:

import pkl

config = pkl.load("path/to/pkl/example_module.pkl")

Code Generation

As Python is a dynamic language, codegen is not strictly necessary. However, codegen lets you expect contents of pkl files within Python modules.

pkl-gen-python path/to/pkl/example_module.pkl

Status

• Evaluator API: functional
• Code Generation: functional, but needs refining

TODO

• (codgen) pip binary installation
• (codgen) gatherer depth-first ordering
• (codgen) clean up code

Advanced Features

For details on the parameters, refer Message Passing API.

import pkl

config = pkl.load("./tests/types.pkl")
config = pkl.load("./tests/types.pkl", expr="datasize")
config = pkl.load(None, module_text="a: Int = 1 + 1")
config = pkl.load("./tests/types.pkl", debug=True)

Custom Readers

It is possible to add module or resource or module readers:

from typing import List
from dataclasses import dataclass

import pkl
from pkl import (
    ModuleReader, ResourceReader, PathElement,
    ModuleSource, PreconfiguredOptions, PklError,
)

class TestModuleReader(ModuleReader):
    def read(self, url) -> str:
        return "foo = 1"

    def list_elements(self, url: str) -> List[PathElement]:
        return [PathElement("foo.pkl", False)]

opts = PreconfiguredOptions(
    moduleReaders=[TestModuleReader("customfs", True, True, True)]
)
opts.allowedModules.append("customfs:")
config = pkl.load("./tests/myModule.pkl", evaluator_options=opts)

Appendix

Type Mappings

While in pre-release they are subject to change.

Pkl type	TypeScript type
Null	None
Boolean	bool
String	str
Int	int
Int8	int
Int16	int
Int32	int
UInt	int
UInt8	int
UInt16	int
UInt32	int
Float	float
Number	float
List	list
Listing	list
Map	dict
Mapping	dict
Set	set
Pair	pkl.Pair
Dynamic	dataclasses.dataclass
DataSize	pkl.DataSize
Duration	pkl.Duration
IntSeq	pkl.IntSeq
Class	dataclasses.dataclass
TypeAlias	typing
Any	typing.Any
Unions (A|B|C)	typing.Union[A|B|C]
Regex	pkl.Regex

Contributing

Contributions are welcome! If you'd like to contribute, please fork the repository and submit a pull request. For major changes, please open an issue first to discuss what you would like to change.

License

PKL is released under the MIT License. See the LICENSE file for more details.

Contact

For support or to contribute, please contact [email protected] or visit our GitHub repository to report issues or submit pull requests.