Introduction to Logos

Logos is a scripting language designed for clarity. When Bash scripts grow past a few dozen lines, Logos is what you reach for — readable syntax, proper error handling, and code you'll still understand next month.

Why Logos?

Bash is fine for one-liners. But as scripts grow, they become unreadable. Logos solves this with:

Readable syntax — C-like structure that reads like English prose, not line noise
Sane error handling — Functions return result objects. Check .ok, handle .error. No silent failures.
Batteries included — File I/O, HTTP, JSON, shell execution all work without imports
Concurrency — spawn blocks run tasks in parallel when order doesn't matter
Compile to binary — lgs build script.lgs produces a standalone executable
Embed in Go — Integrate into your Go applications like Lua or JavaScript

A Taste of Logos

Here's a script that reads a config file, parses JSON, uses string interpolation, and runs tasks concurrently:

example.lgs

// Fetch config, handle errors gracefully
let res = fileRead("config.json")
if !res.ok {
    print(colorRed("Error: " + res.error))
    exit(1)
}

let config = try parseJson(res.value)

// String interpolation makes templates readable
let greeting = "Hello, ${config["name"]}! Your plan: ${config["plan"]}"

// Ternary for simple conditions
let status = config["active"] ? "active" : "inactive"
print("${status} - ${greeting}")

// Dot assignment mutates table fields
config["version"] = "2.0"

// For-in with index for numbered lists
let tasks = ["build", "test", "deploy"]
for i, task in tasks {
    print("${i + 1}. ${task}")
}

// Range with step (0 to 10, exclusive)
for i in range(0, 10, 2) {
    print(i)  // 0, 2, 4, 6, 8
}

// Run tasks concurrently when order doesn't matter
spawn for task in tasks {
    processTask(task)
}

CLI Commands

Run scripts, format code, or build binaries:

bash

lgs hello.lgs        # Run a script
lgs fmt script.lgs    # Format code (auto-fixes indentation)
lgs build script.lgs  # Compile to standalone binary
lgs                   # Start the REPL for quick experiments