{"id":7845,"library":"varint","title":"Python Varint Implementation","description":"The `varint` library provides a simple Python implementation for variable-length encoding and decoding of integers. This encoding scheme is primarily useful for creating more compact representations, particularly for sequences or arrays of frequently small integers, to save memory. While Python's native integer objects have overhead, varint encoding can be advantageous when storing many small numbers in a bytearray.","status":"maintenance","version":"1.0.2","language":"en","source_language":"en","source_url":"http://github.com/fmoo/python-varint","tags":["varint","encoding","decoding","variable-length integer","compression","serialization"],"install":[{"cmd":"pip install varint","lang":"bash","label":"Install latest version"}],"dependencies":[],"imports":[{"note":"For encoding a single integer into varint bytes.","symbol":"encode","correct":"from varint import encode"},{"note":"For decoding varint bytes directly from a bytes-like object.","symbol":"decode_bytes","correct":"from varint import decode_bytes"},{"note":"For decoding varint bytes from a file-like object (stream).","symbol":"decode_stream","correct":"from varint import decode_stream"}],"quickstart":{"code":"from varint import encode, decode_bytes, decode_stream\nfrom io import BytesIO\n\n# Encode an integer\nnumber_to_encode = 300\nencoded_bytes = encode(number_to_encode)\nprint(f\"Encoded {number_to_encode}: {encoded_bytes.hex()}\")\n\n# Decode from bytes\ndecoded_number_from_bytes = decode_bytes(encoded_bytes)\nprint(f\"Decoded from bytes: {decoded_number_from_bytes}\")\n\n# Decode from a stream\nstream = BytesIO(encoded_bytes)\ndecoded_number_from_stream = decode_stream(stream)\nprint(f\"Decoded from stream: {decoded_number_from_stream}\")\n\n# Example with a larger number\nlarge_number = 123456789\nencoded_large = encode(large_number)\nprint(f\"\\nEncoded {large_number}: {encoded_large.hex()}\")\ndecoded_large = decode_bytes(encoded_large)\nprint(f\"Decoded large number: {decoded_large}\")","lang":"python","description":"This example demonstrates how to encode an integer into variable-length bytes and then decode it back using both `decode_bytes` for a direct bytes object and `decode_stream` for a file-like object (BytesIO)."},"warnings":[{"fix":"Evaluate actual memory usage for your specific use case, especially for single integer storage, and consider the processing overhead incurred by encoding/decoding. This library is best for sequences of small integers.","message":"Using varint encoding for individual integers in Python can *increase* memory usage due to Python's object and `bytearray` overhead, rather than reducing it. The memory benefit is primarily realized when encoding and storing *arrays or lists* of many small integers.","severity":"gotcha","affected_versions":"All versions"},{"fix":"For new projects, consider more actively maintained alternatives if specific performance or modern Python feature support is critical. For existing projects, be aware of the lack of ongoing development.","message":"The `varint` library has not seen updates since its last release on February 24, 2016. While functional, this means it may not incorporate newer Python features, performance optimizations, or receive bug fixes.","severity":"deprecated","affected_versions":"1.0.2 and earlier"},{"fix":"Benchmark and profile your application to ensure the memory savings (if any) outweigh the computational cost of encoding and decoding, particularly for high-throughput scenarios.","message":"There is a processing overhead associated with encoding and decoding integers using varint. This library is not a drop-in replacement for native integer storage if raw performance and direct random access are paramount.","severity":"gotcha","affected_versions":"All versions"}],"env_vars":null,"last_verified":"2026-04-16T00:00:00.000Z","next_check":"2026-07-15T00:00:00.000Z","problems":[{"fix":"Install the library using pip: `pip install varint`","cause":"The `varint` library has not been installed or is not accessible in the current Python environment.","error":"ImportError: No module named 'varint'"},{"fix":"Ensure that you are passing a `bytes` object (e.g., `b'\\xc2\\x02'`) to `decode_bytes` or a `BytesIO` stream to `decode_stream`, not the raw integer value.","cause":"Attempting to pass an integer directly to `decode_bytes` or `decode_stream` instead of a bytes object or a stream.","error":"TypeError: argument must be a bytes-like object, not 'int' or TypeError: expected a bytes-like object, not int"},{"fix":"Verify that the byte stream contains valid and complete varint-encoded data. This often happens if the stream is consumed or positioned incorrectly before decoding.","cause":"The `decode_stream` function attempted to read beyond the end of the provided stream, indicating incomplete or malformed varint data.","error":"EOFError: Read from empty stream"}]}