plum-py

0.8.7 verified Fri May 01 auth: no python

Pack/Unpack Memory. A Python library for packing and unpacking binary data structures, similar to struct but with higher-level features. Current version 0.8.7, release cadence is low (last release August 2022).

pip install plum-py

Common errors

error ImportError: No module named 'plum_py' ↓

cause Trying to import with the PyPI package name instead of the module name.

fix

Use 'import plum' or 'from plum import Struct'.

error TypeError: __init__() got an unexpected keyword argument 'field_name' ↓

cause Attempting to set fields via constructor with Python-typed field names, but the library expects specific names derived from format strings.

fix

Ensure field names match class attributes defined with format strings.

Warnings

gotcha The import is 'from plum import Struct', not 'plum-py' or 'plum_py'. The PyPI name is plum-py but the module name is plum. ↓

fix Use 'from plum import Struct'.

gotcha Field types are specified as strings (e.g., 'I' for unsigned int) similar to struct module. Using Python type hints does not work; you must use struct format characters. ↓

fix Define fields as class-level annotations with format strings, e.g., field_name: 'I'.

gotcha The Struct class does not support variable-length arrays or nested structs directly. Use custom pack/unpack methods. ↓

fix For complex structures, consider using construct or raw struct.

Imports

Struct

wrong

from plum_py import Struct

correct

from plum import Struct

Package name is plum, not plum-py.

Quickstart

Define a struct with fields and pack into bytes.

from plum import Struct

class MyHeader(Struct):
    magic: 'I'  # unsigned int
    length: 'I'
    data: 'I'

hdr = MyHeader(magic=0x1234, length=100, data=0)
buffer = hdr.pack()
print(buffer.hex())