Redlines

0.6.1 · active · verified Wed Apr 15

Redlines is a Python library that compares two strings or blocks of text, producing human-readable differences or 'deltas' similar to Microsoft Word's track changes. It provides structured output showing detailed change information, positions, and statistics, supporting various formats like JSON (default for CLI), Markdown, HTML, and rich terminal display. The current version is 0.6.1, and the project exhibits an active release cadence.

Warnings

breaking The command-line interface (CLI) behavior changed significantly in v0.6.0. It is now command-less by default and outputs JSON. Previous versions might have had different default outputs or required specific subcommands.
Fix: Review the official 'Agent Integration Guide' or run `redlines --help` for the new CLI syntax. Expect JSON output by default when calling `redlines "old text" "new text"`.
gotcha This `redlines` library is for comparing general text strings. There is a similarly named, but distinct, `Python-Redlines` project (not on PyPI) focused specifically on `.docx` file comparison. Ensure you are installing the correct library for your use case.
Fix: Verify the PyPI page and documentation to confirm `redlines` (pypi.org/project/redlines) is the correct library for generic text comparison, not `.docx` files.
gotcha Advanced features like intelligent sentence detection (for Python 3.11+) and Levenshtein distance statistics require installing optional dependencies using `pip install redlines[nupunkt]` or `pip install redlines[levenshtein]` respectively. These features are not available with a basic `pip install redlines`.
Fix: Install the library with the appropriate extra, e.g., `pip install redlines[nupunkt]` to access `NupunktProcessor` for advanced tokenization.

Install

pip install redlines Standard Install
pip install redlines[nupunkt] With advanced sentence detection (Python 3.11+)
pip install redlines[levenshtein] With Levenshtein distance statistics

Imports

Redlines
```
from redlines import Redlines
```

Quickstart

Instantiate the `Redlines` class with two strings to compare. The class provides methods like `output_markdown`, `output_json`, and `output_rich` for different output formats. The `compare` method can be used for subsequent comparisons against the initial 'old' text.

from redlines import Redlines

old_text = "The quick brown fox jumps over the lazy dog."
new_text = "The quick brown fox walks past the lazy cat."

# Create a Redlines object
comparator = Redlines(old_text, new_text)

# Get markdown output with <del>/<ins> tags
markdown_output = comparator.output_markdown
print(f"Markdown Output:\n{markdown_output}\n")

# Get JSON output (structured data)
json_output = comparator.output_json()
print(f"JSON Output:\n{json_output}\n")

# Example of using the compare method for multiple comparisons
alternate_new_text = "The quick brown fox sleeps near the lazy dog."
compare_output = comparator.compare(alternate_new_text)
print(f"Comparison with alternate text:\n{compare_output}")

view raw JSON →