# Trait std::marker::Sized [−] [src]

    pub trait Sized { }

Types with a constant size known at compile-time.

All type parameters which can be bounded have an implicit bound of `Sized`. The special syntax `?Sized` can be used to remove this bound if it is not appropriate.

fn main() { #![allow(dead_code)] struct Foo<T>(T); struct Bar<T: ?Sized>(T); // struct FooUse(Foo<[i32]>); // error: Sized is not implemented for [i32] struct BarUse(Bar<[i32]>); // OK }

    struct Foo<T>(T);
    struct Bar<T: ?Sized>(T);

    // struct FooUse(Foo<[i32]>); // error: Sized is not implemented for [i32]
    struct BarUse(Bar<[i32]>); // OK

## Implementors

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