gt

A command-line calculator with percentage calculations and RPN (Reverse Polish Notation) stack arithmetic, written in Go.

This is a toy project to experiment with local LLMs (Qwen, Gemma, Nemotron, GPT OSS) as pair programmers.

Installation

go install codeberg.org/snonux/gt/cmd/gt@latest

Or using mage:

mage install

Quick Start

gt '20% of 150'         # → 30
gt '3 4 +'              # RPN: 3 + 4 → 7
gt 'pi 2 *'             # 2π → 6.283185307
gt '100Mbps 1hr *'      # rate × time → 3.6e+11 bits
gt                      # interactive REPL

Shell Completions

Fish completions are available in completions/. To install:

cp completions/gt.fish ~/.config/fish/completions/

Or system-wide:

sudo cp completions/gt.fish /usr/local/share/fish/vendor_completions.d/

Feature Guide

All features are documented in docs/:

Topic	Doc
CLI modes, piping, REPL	cli-usage
Percentage calculations	percentage-calculations
RPN basics	basic-arithmetic
Fast integer power (**)	fast-power
Logarithm operators	log-operators
Hyper (n-ary) operators	hyper-operators
Comparisons and booleans	comparisons
Variables and assignment	variables
Symbols (:x syntax)	symbols
Built-in constants	constants
Stack manipulation	stack-operations
Metrics and units	metrics
Unit conversion	unit-conversion
Metric commands	metric-commands
Custom metrics	custom-metrics
REPL mode	repl-mode
Rational number mode	rational-mode
Fish shell completions	completions

Building and Testing

mage build      # Build the binary
mage test       # Run all tests

License

See LICENSE for details.