forked from Orchid/orchid
25 lines
718 B
Rust
25 lines
718 B
Rust
//! The concept of a fallible merger
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use never::Never;
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/// Fallible, type-preserving variant of [std::ops::Add] implemented by a
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/// variety of types for different purposes. Very broadly, if the operation
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/// succeeds, the result should represent _both_ inputs.
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pub trait Combine: Sized {
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/// Information about the failure
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type Error;
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/// Merge two values into a value that represents both, if this is possible.
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fn combine(self, other: Self) -> Result<Self, Self::Error>;
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}
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impl Combine for Never {
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type Error = Never;
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fn combine(self, _: Self) -> Result<Self, Self::Error> { match self {} }
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}
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impl Combine for () {
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type Error = Never;
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fn combine(self, (): Self) -> Result<Self, Self::Error> { Ok(()) }
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}
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