Norvelang

Multi-Source Data Processing Language

Features

• PEMDAS-compliant mathematical expressions
• String functions (upper, lower, len, contains, etc.)
• SQL-like pipelines for CSV, JSON, XML, SQLite, Excel
• Filtering and aggregation with grouping and joins
• Function support in use and where clauses
• Robust join handling with automatic column disambiguation
• Clean, extensible grammar
• CLI and Python API for interactive and programmatic use

Quick Start

data.csv | use name, age | where age > 30

Installation

uv venv
.venv\Scripts\activate
uv pip install -r .\requirements.txt

Usage

Command Line

# Run a sample file
python -m norve samples/math.nv

# Interactive REPL
python -m norve

# Use regular Lark parser (disable cython)
python -m norve samples/queries.nv --no-lark-cython

Python API

import norve

df = norve.execute_query('''data.csv | use name, age | limit 10''')
output = norve.execute_with_output('''data.csv | use name, age | limit 5''')
variables = {'my_table': 'users.csv'}
df = norve.execute_query('''let users = $my_table; $users | use name, age | limit 10''', variables=variables)

Directory Structure

norvelang/
├── norve/              # Core language implementation
│   ├── api/            # Python API
│   ├── ast/            # AST definitions
│   ├── error/          # Error handling
│   ├── interpreter/    # Pipeline execution
│   ├── transformer/    # AST transformation
│   ├── grammar.lark    # Grammar definition
│   └── *.py            # Core modules
├── publish/            # Create new release on Github and PyPI
├── samples/            # Example .nv files
├── sample_data/        # Test data files
├── tests/              # Unit tests
├── requirements.txt    # Python dependencies
└── README.md           # This file

Running Tests

cd tests
pytest -v

Sample Files

• math.nv: Math and function demos
• queries.nv, queries2.nv: Data processing examples
• data_sources.nv: Multi-format data
• errors.nv: Error handling