If I want to build a custom vtable containing function pointers, I can do this: use std::fmt::Display; struct Vtable { to_string: unsafe fn(*const ()) -> String, } fn vtable_for_type<T: Display>() -> &'static Vtable { &Vtable { to_string: to_string::<T>, } } unsafe fn to_stri…

Interesting. The 1414-rvalue_static_promotion - The Rust RFC Book RFC claims These rules above should be consistent with the existing rvalue promotions in const initializer expressions: // If this compiles: const X: &'static T = &<constexpr foo>; // Then this should compile as well: let x: &'sta…

Custom vtables with integers

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krdln July 18, 2022, 3:20pm 7

const-block also seems to make it compile! (playground)

        value_size: const { compute_value_size::<T>() },

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Custom vtables with integers

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