chaf

Crates.io	chaf
lib.rs	chaf
version	0.1.0
created_at	2025-08-08 11:58:24.433587+00
updated_at	2025-08-08 11:58:24.433587+00
description	A CLI filter tool that removes lines based on logical conditions using AND, OR, NOT, and parentheses.
homepage
repository	https://github.com/nakkiy/chaf
max_upload_size
id	1786679
size	63,350

(nakkiy)

documentation

https://github.com/nakkiy/chaf

README

`chaf` – Not a finder. A filter.

✨ What is chaf?

chaf is a text filtering tool with the following features:

Logical expressions for condition specification
Instead of "searching" like grep, it "excludes" specified lines
Supports standard input/output, making it pipe-friendly
Uses stdin when no input file is provided
Invert exclusion with --invert to act like grep
Display summary report with --report
Not as fast as grep, but can process ~10 million lines in a few seconds

💡 Why was it created?

While grep -v is convenient, expressing complex exclusion rules becomes unreadable.
For example: "Exclude DEBUG, but keep [DEBUG] connect DB"
Such conditions are difficult to express clearly with grep.

chaf lets you write exclusion logic with logical expressions — a filter dedicated to exclusion.

🖥️ Example Usage

## 🖥️ Example Usage

```bash
$ cat logs.txt
error: failed to connect
warn: deprecated API used
debug: retrying connection
info: connection established
warn: low disk space
error: timeout while waiting for response

# Lines containing "debug" or "warn" are excluded
$ chaf 'debug | warn' logs.txt
error: failed to connect
info: connection established
error: timeout while waiting for response

# Excludes:
# - Lines containing "debug"
# - Lines containing "warn" unless they also contain "API"
$ chaf 'debug | (warn & !API)' logs.txt
error: failed to connect
warn: deprecated API used
info: connection established
error: timeout while waiting for response
# Explanation:
# → "warn: low disk space" is excluded (no "API")
# → "warn: deprecated API used" is kept (contains "API")

# Invert mode: show only lines that match the condition
# Includes:
# - Lines containing "debug"
# - Lines containing "warn" unless they also contain "API"
$ chaf --invert 'debug | (warn & !API)' logs.txt
debug: retrying connection
warn: low disk space

🚀 Installation

cargo install --git https://github.com/nakkiy/chaf

The chaf binary will be placed in:

$HOME/.cargo/bin/chaf

If your PATH doesn't include that directory, add it like so:

export PATH="$HOME/.cargo/bin:$PATH"

✔ Command-Line Interface

chaf [OPTIONS] <QUERY> [FILE]

📝 Query DSL (Logical Filter Language)

Syntax	Meaning
`aaa & bbb`	AND — match lines containing both `aaa` and `bbb` (exclude)
`aaa \| bbb`	OR — match lines containing either `aaa` or `bbb` (exclude)
`!aaa`	NOT — match lines not containing `aaa` (exclude)
`(aaa \| bbb)`, `(aaa & bbb)`	Use parentheses to group and control precedence

Operator Precedence

1. Parentheses "()"
2. NOT "!"
3. AND "&"
4. OR "|"

🎛️ Available Options

Option	Description
`--report`, `-r`	Show summary: total lines, excluded lines, output lines
`--invert`, `-i`	Invert filter to show matching lines only (like `grep`)
`--help`, `-h`	Show help message
`--version`, `-v`	Show version information

Tip: You can redirect output to a file with > if needed.

🙌 Contributing

Contributions for improvements or feature expansions are very welcome!
Feel free to open an issue or PR if you have any feedback or suggestions —
no matter how small, we'd love to hear from you.

🔮 Planned Features

Wildcard support (*, ?) for more flexible pattern matching

✅ License

This project is dual-licensed under:

Use whichever license suits your needs.

Commit count: 0