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 }

index.nct

//! Algorithm-neutral hashing contracts.
//!
//! Values contribute their complete logical representation to an opaque state. Hash output,
//! seeding, and algorithm selection remain package-internal implementation details.

use /string.String
use /vec.Vec
see ./state.nct
see ./scalars.nct
see ./implementations.nct

/// Opaque state selected and initialized by the standard library.
pub struct HashState

construct HashState {
    /// Creates a hidden random seed template for package-internal associative storage.
    pub(/) func fresh(): Self
}

/// Values whose equality classes can be used as associative-collection keys.
pub interface Hash where (&Self == &Self): bool {
    /// Contributes the complete equality-relevant value without allocation.
    pub noalloc method &self.hash_into(state: &+HashState): void
}

instance HashState {
    /// Contributes an exact byte sequence to this state.
    pub noalloc method &+self.write(bytes: &[u8]): void

    /// Starts an independent hash with this state's retained seed.
    pub(/) noalloc method &self.restart(): Self

    /// Finalizes the current contribution without exposing mutable state.
    pub(/) noalloc method &self.finish(): u64
}

instance bool {
    impl Hash
}

instance char {
    impl Hash
}

instance i8 {
    impl Hash
}

instance i16 {
    impl Hash
}

instance i32 {
    impl Hash
}

instance i64 {
    impl Hash
}

instance isize {
    impl Hash
}

instance u8 {
    impl Hash
}

instance u16 {
    impl Hash
}

instance u32 {
    impl Hash
}

instance u64 {
    impl Hash
}

instance usize {
    impl Hash
}

instance str {
    impl Hash
}

instance String {
    impl Hash
}

instance [T] where T impl Hash {
    impl Hash
}

instance Vec<T> where T impl Hash {
    impl Hash
}