47 lines
932 B
Rust
47 lines
932 B
Rust
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//xfail-test
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// Sketching traits.
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// methods with no implementation are required; methods with an
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// implementation are provided. No "req" keyword necessary.
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trait Eq {
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fn eq(a: self) -> bool;
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fn neq(a: self) -> bool {
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!self.neq(a)
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}
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}
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// The `<` is pronounced `extends`. Also under consideration is `<:`.
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// Just using `:` is frowned upon, because (paraphrasing dherman) `:`
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// is supposed to separate things from different universes.
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trait Ord < Eq {
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fn lt(a: self) -> bool;
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fn lte(a: self) -> bool {
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self.lt(a) || self.eq(a)
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}
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fn gt(a: self) -> bool {
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!self.lt(a) && !self.eq(a)
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}
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fn gte(a: self) -> bool {
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!self.lt(a)
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}
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}
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// pronounced "impl of Ord for int" -- not sold on this yet
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impl int: Ord {
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fn lt(a: self) -> bool {
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self < a
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}
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// is this the place to put this?
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fn eq(a: self) -> bool {
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self == a
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}
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}
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