18 lines
442 B
Rust
18 lines
442 B
Rust
#![feature(core_intrinsics)]
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extern crate core;
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use core::intrinsics::discriminant_value;
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#[repr(usize)]
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enum MyWeirdOption<T> {
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//~^ ERROR parameter `T` is never used
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None = 0,
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Some = std::mem::size_of::<T>(),
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//~^ ERROR generic parameters may not be used in const operations
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}
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fn main() {
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assert_eq!(discriminant_value(&MyWeirdOption::<u8>::None), 0);
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assert_eq!(discriminant_value(&MyWeirdOption::<u8>::Some), 1);
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}
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