Brandon Lucas
b0f6756411
Adds two essential effects that enable Lux to interact with the system:
File effect:
- read(path) - Read file contents as string
- write(path, content) - Write string to file
- append(path, content) - Append to file
- exists(path) - Check if file/directory exists
- delete(path) - Delete a file
- readDir(path) - List directory contents
- isDir(path) - Check if path is directory
- mkdir(path) - Create directory (including parents)
Process effect:
- exec(cmd) - Run shell command, return stdout
- execStatus(cmd) - Run command, return exit code
- env(name) - Get environment variable (returns Option)
- args() - Get command line arguments
- exit(code) - Exit program with code
- cwd() - Get current working directory
- setCwd(path) - Change working directory
Also fixes formatter bug with empty handler blocks in `run ... with {}`.
These effects make Lux capable of writing real CLI tools and scripts.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
// Shell/Process example - demonstrates the Process effect
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//
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// This script runs shell commands and uses environment variables
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fn main(): Unit with {Process, Console} = {
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Console.print("=== Lux Shell Example ===")
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Console.print("")
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// Get current working directory
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let cwd = Process.cwd()
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Console.print("Current directory: " + cwd)
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Console.print("")
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// Get environment variables
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Console.print("Environment variables:")
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match Process.env("USER") {
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Some(user) => Console.print(" USER: " + user),
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None => Console.print(" USER: (not set)")
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}
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match Process.env("HOME") {
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Some(home) => Console.print(" HOME: " + home),
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None => Console.print(" HOME: (not set)")
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}
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match Process.env("SHELL") {
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Some(shell) => Console.print(" SHELL: " + shell),
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None => Console.print(" SHELL: (not set)")
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}
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Console.print("")
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// Run shell commands
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Console.print("Running shell commands:")
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let date = Process.exec("date")
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Console.print(" date: " + String.trim(date))
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let kernel = Process.exec("uname -r")
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Console.print(" kernel: " + String.trim(kernel))
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let files = Process.exec("ls examples/*.lux | wc -l")
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Console.print(" .lux files in examples/: " + String.trim(files))
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Console.print("")
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// Command line arguments
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Console.print("Command line arguments:")
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let args = Process.args()
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let argCount = List.length(args)
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if argCount == 0 then {
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Console.print(" (no arguments)")
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} else {
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Console.print(" Count: " + toString(argCount))
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match List.head(args) {
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Some(first) => Console.print(" First: " + first),
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None => Console.print(" First: (empty)")
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}
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}
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}
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let result = run main() with {}
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