use std/io use std/vec.Vec struct Counter { value: i32 } blocking func main(): i32! { var counters = Vec [Counter { value: 1 }, Counter { value: 2 }, Counter { value: 3 }] for counter in &+counters { counter.value += 10 } var borrowed_total: i32 = 0 for counter in &counters { borrowed_total += counter.value } var moved_total: i32 = 0 for counter in move counters { moved_total += counter.value } let message = "borrowed: ${borrowed_total}, moved: ${moved_total}\n" io.print(&message)? return 0 }

func main(): i32 { let value = load_value() catch failure { fallback_for(failure.message()) } if value == 42 { return 0 } return 1 } func load_value(): i32! { return error.new("example.unavailable", "the primary value is unavailable") } func fallback_for(message: &str): i32 { return 42 }

use std/task use std/time use std/time.Duration async func delayed(value: i32): i32 { await time.sleep(Duration.from_milliseconds(1)) return value } async func main(): i32! { let (left, right) = await task.join(delayed(20), delayed(22)) if left + right != 42 { return error.new("example.unexpected_total", "joined tasks returned the wrong total") } return 0 }

use std/io use std/url.Url blocking func main(): i32! { let url = Url.parse("HTTP://Example.COM:80/a/../status?q=ready#fragment")? let canonical = url.to_string() let authority = url.authority() let target = url.request_target() io.println(&canonical)? io.println(&authority)? io.println(&target)? return 0 }

nocter-installation

Responsibility

Locate and validate one installed Nocter home and install one already acquired, explicitly trusted release artifact through a recoverable filesystem transaction.

Contract

The crate consumes explicit or process-derived installation paths and returns immutable validated installation facts, or an explicit local artifact-install request and result. Command and workspace layers use those contracts; compiler stages never inspect the environment or installation layout themselves. This crate neither downloads artifacts nor chooses which digest to trust.

Internal Responsibilities

real executable and Nocter-home resolution
exact manifest v2 decoding and component digest validation
compiler/standard-package compatibility
installed package-root location
exact archive-byte verification and candidate-home validation
same-parent fresh publication, active-home replacement, and interrupted-transaction recovery

Invariants

The manifest binds the exact compiler file and complete regular standard-library tree.
Standard-library validation consumes the language-owned module-root file name.
A configured home accepts the running compiler only when its digest equals the manifest-bound compiler digest.
Environment and executable-path reads occur at the outer boundary.
Invalid, corrupted, or partially updated homes cannot supply a toolchain snapshot.
The bytes checked against the caller's digest are the same immutable bytes passed to extraction.
A candidate is completely validated before the destination changes.
An existing destination can be replaced only when it is the active validated home.
Unmarked transaction paths are never treated as installer-owned state.

nocter-installation#

Responsibility#

Contract#

Internal Responsibilities#

Invariants#

nocter-installation

Responsibility

Contract

Internal Responsibilities

Invariants