csv

RFC-4180 compliant CSV and TSV parser, serializer, and data processor for Alya.

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🌟 Features

• ⚡ High Performance: Native parsing and stringification reaching over 1M ops/sec.
• 📜 RFC-4180 Compliant: Handles commas inside quotes, CRLF/LF line endings, escaped double quotes (""), and multiline fields.
• 📑 Header-to-Map Records: Automatically maps header rows into structured dictionary records ([ {"name": "Alice", "role": "Dev"} ]).
• 🔄 Custom Delimiters: Built-in support for CSV (,), TSV (\t), Semicolon (;), and custom delimiters.
• 📁 File I/O: Direct helpers to read and write rows or records to files.

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📁 Project Architecture

csv/
├── alya.toml               # Package manifest
├── src/
│   ├── lib.alya            # Public API facade
│   ├── types.alya          # CsvOptions configuration struct & constructors
│   ├── core/
│   │   ├── parser.alya     # State-machine RFC-4180 CSV / TSV parser & record mapper
│   │   └── writer.alya     # CSV / TSV serializer & field escaping
│   └── io/
│       └── file.alya       # File read / write operations
├── examples/
│   └── demo.alya           # Comprehensive runnable demo
├── tests/
│   └── test_basic.alya     # 47 RFC-4180 automated test cases
└── benches/
    └── bench_basic.alya    # Micro-benchmarks

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📦 Installation

Add csv to the [dependencies] section in your alya.toml:

[dependencies]
csv = { git = "https://github.com/alya-lang/csv", branch = "main" }

Or install it directly using the Alya package CLI:

alya add csv --git https://github.com/alya-lang/csv --branch main
alya install

Package Features

Feature	Default	Description
io	✅	File I/O (read_file_rows/read_file_records/write_file_rows/write_file_records). Without it only in-memory parse/stringify remain.

# Full build (default)
alya install
alya test

# Slim build without file I/O
alya install --no-default-features
alya test --no-default-features

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🚀 Quick Start

1. Basic Parsing & Stringification

import "csv"

function main()
    let raw = "name,role,city\nAlice,Engineer,\"New York, NY\"\nBob,Lead,London"

    # Parse into 2D row array
    let rows = csv::parse_csv(raw)
    say "First person: " + rows[1][0] # Alice

    # Serialize back to CSV
    let output = csv::stringify_csv(rows)
    say output
end

main()

2. Working with Map Records

import "csv"

function main()
    let raw = "id,product,price\n101,Laptop,1200\n102,Mouse,25"
    let records = csv::parse_csv_records(raw)

    let i = 0
    while i < len(records)
        let item = records[i]
        say "Item: " + item["product"] + " -> $" + item["price"]
        i += 1
    end

    # Serialize records with specific column order
    let headers = ["id", "product", "price"]
    let csv_text = csv::stringify_csv_records(records, headers)
    say csv_text
end

main()

3. File Operations

import "csv"

function main()
    let path = "./inventory.csv"
    let rows = [
        ["sku", "name", "qty"],
        ["A01", "Keyboard", "50"],
        ["B02", "Monitor", "20"]
    ]

    # Write rows to file
    csv::write_file_rows(path, rows)

    # Read rows back
    let loaded = csv::read_file_rows(path)
    say "Total rows: " + str(len(loaded))
end

main()

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📖 API Reference

Options Constructors

Function	Arguments	Returns	Description
options()	-	CsvOptions	Returns default CSV options (, delimiter, CRLF disabled, trim disabled).
tsv_options()	-	CsvOptions	Returns TSV options (\t delimiter).
custom_options(delimiter)	delimiter: string	CsvOptions	Returns options with a custom delimiter character.

Parsing Functions

Function	Arguments	Returns	Description
parse_csv(text, opts = null)	text: string, opts: CsvOptions	array	Parses CSV text into a 2D array of rows.
parse_tsv(text, opts = null)	text: string, opts: CsvOptions	array	Parses TSV text into a 2D array of rows.
parse_csv_records(text, opts = null)	text: string, opts: CsvOptions	array	Parses CSV text into a list of Map records using the header row.
parse_tsv_records(text, opts = null)	text: string, opts: CsvOptions	array	Parses TSV text into a list of Map records using the header row.

Serialization Functions

Function	Arguments	Returns	Description
stringify_csv(rows, opts = null)	rows: array, opts: CsvOptions	string	Serializes a 2D array of rows into CSV text.
stringify_tsv(rows, opts = null)	rows: array, opts: CsvOptions	string	Serializes a 2D array of rows into TSV text.
stringify_csv_records(records, headers = null, opts = null)	records: array, headers: array, opts: CsvOptions	string	Serializes Map records into CSV text with headers.
stringify_tsv_records(records, headers = null, opts = null)	records: array, headers: array, opts: CsvOptions	string	Serializes Map records into TSV text with headers.

File I/O Functions

Function	Arguments	Returns	Description
read_file_rows(path, opts = null)	path: string, opts: CsvOptions	array	Reads and parses rows directly from a CSV file.
read_file_records(path, opts = null)	path: string, opts: CsvOptions	array	Reads and parses Map records directly from a CSV file.
write_file_rows(path, rows, opts = null)	path: string, rows: array, opts: CsvOptions	int	Serializes rows and writes to a CSV file.
write_file_records(path, records, headers = null, opts = null)	path: string, records: array, headers: array, opts: CsvOptions	int	Serializes Map records and writes to a CSV file.

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🧪 Running Tests & Benchmarks

Run the test suite using alya:

alya test
# or
alya run tests/test_basic.alya

Run the benchmark suite:

alya run benches/bench_basic.alya

Run the example demo:

alya run examples/demo.alya

Check code formatting:

alya fmt . --check

Run static code linter:

alya lint . --check

🤝 Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository and clone it locally
2. Install dependencies:

   alya install

3. Create your feature branch (git checkout -b feature/my-feature)
4. Verify tests and formatting before opening a PR:

   alya test
   alya fmt . --check

5. Commit your changes (git commit -m "feat: add feature") and open a Pull Request

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📄 License

This project is licensed under the MIT License - see the LICENSE file for details.