Command Line and Processes

std.cli implements argument parsing in Norm. std.application, standard streams, and std.process reuse the system runtime without adding third-party dependencies.

Arguments and execution environment

import std.application.arguments
import std.cli.CommandLine
import std.cli.Option
import std.cli.OptionKind

Void main() {
  CommandLine command = CommandLine(name: "gait", description: "Git assistant", options: [
    Option(name: "json", description: "JSON output", kind: OptionKind.Flag),
    Option(name: "repo", description: "Repository directory", kind: OptionKind.Value)
  ])
  var parsed = command.parse(arguments: arguments(), stopAtPositional: true)
  printLine(parsed.value(name: "repo") ?? ".")
}

When running sources, use norm run application.norm -- --repo "my repo" create-branch. A generated application receives arguments directly. The parser consumes an existing argument array, preserving spaces and empty strings; definitions, help text, and parsing rules share the same option set.

See std.cli for public declarations and failure types. std.application defines environment variables, working directory, arguments, and completion codes. setExitCode sets the code returned after normal completion without interrupting resource cleanup.

Standard streams and child processes

std.io.console provides borrowed standard input and text output; applications cannot close the host standard streams. Byte reads and UTF-8 conversion reuse the I/O protocol.

On a Windows console, native applications read and write through Unicode APIs and convert input to UTF-8 bytes without changing the terminal code page. Stdout and stderr detect console handles independently and emit UTF-8 when redirected to a file or pipe. See NativeStandardStreams for the host implementation.

std.process starts child processes with an executable and argument array, without a shell. Nonzero exit, timeout, and cancellation are results; invalid requests, startup failures, and I/O failures are catchable exceptions. Separate output budgets apply to stdout and stderr; excess output is drained and the result marks it as truncated.

Process exit does not roll back external effects. Cancellation and timeout terminate the managed process and observed descendants; this is not operating-system-level process isolation. Callers must still verify the actual result of external operations such as Git.

Acceptance entry points: arguments and standard streams and real child processes.