Initializable

Defines the canonical variadic runtime-initialization requirement.

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Module std.prelude

import std.prelude;

Public declaration contracts and authored examples. A page can document several related symbols. Implementation bodies are excluded.

Initializable

pub concept Initializable<Self, each A>

Defines the canonical variadic runtime-initialization requirement.

Satisfaction is structural and compile-time-only. The ordered argument pack selects one ordinary initializer and creates no runtime witness, allocation, or source-visible constructor object.

Self: Concrete value type whose initializer is required. A: Ordered final pack of initializer argument types and access modes.

Example

module example.initializable;
from std.prelude import Initializable;
pub struct Counter {
    pub Value: i32;
    pub init(Value: i32) { this.Value = Value; }
}
fn Create<T>(Value: i32) -> T
    where T: Initializable<i32>
{
    return T(Value);
}
fn Main() -> i32 {
    let Value = Create<Counter>(42);
    return Value.Value - 42;
}

Initializable.requirement

requires init(each Argument: A);

Requires one initializer applicable to the complete ordered pack.

Documentation snapshot: October 24, 2026 About versions ↗