20 lines
530 B
Rust
20 lines
530 B
Rust
// Tests that impl methods are matched to traits exactly:
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// we might be tempted to think matching is contravariant, but if
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// we let an impl method can have more permissive bounds than the trait
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// method it's implementing, the return type might be less specific than
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// needed. Just punt and make it invariant.
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use iter::BaseIter;
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trait A {
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fn b<C:Copy Const, D>(x: C) -> C;
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}
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struct E {
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f: int
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}
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impl E: A {
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fn b<F:Copy, G>(_x: F) -> F { fail } //~ ERROR in method `b`, type parameter 0 has 1 bound, but
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}
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fn main() {} |