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10c8b7c1d7
When comparing a value whose type is a type parameter to an interface, we need to convert that type parameter to an interface using the dictionary entries. Change-Id: I409c9e36e376fe4ef8163407d0fd4e84496d5b65 Reviewed-on: https://go-review.googlesource.com/c/go/+/334150 Trust: Keith Randall <khr@golang.org> Trust: Dan Scales <danscales@google.com> Run-TryBot: Keith Randall <khr@golang.org> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Dan Scales <danscales@google.com>
72 lines
1.3 KiB
Go
72 lines
1.3 KiB
Go
// run -gcflags=-G=3
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// Copyright 2021 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// comparisons of type parameters to interfaces
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package main
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func f[T comparable](t, u T) bool {
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// Comparing two type parameters directly.
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// (Not really testing comparisons to interfaces, but just 'cause we're here.)
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return t == u
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}
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func g[T comparable](t T, i interface{}) bool {
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// Compare type parameter value to empty interface.
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return t == i
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}
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type I interface {
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foo()
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}
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type C interface {
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comparable
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I
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}
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func h[T C](t T, i I) bool {
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// Compare type parameter value to nonempty interface.
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return t == i
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}
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type myint int
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func (x myint) foo() {
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}
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func k[T comparable](t T, i interface{}) bool {
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// Compare derived type value to interface.
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return struct{a, b T}{t, t} == i
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}
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func main() {
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assert(f(3, 3))
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assert(!f(3, 5))
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assert(g(3, 3))
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assert(!g(3, 5))
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assert(h(myint(3), myint(3)))
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assert(!h(myint(3), myint(5)))
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type S struct { a, b float64 }
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assert(f(S{3,5}, S{3,5}))
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assert(!f(S{3,5}, S{4,6}))
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assert(g(S{3,5}, S{3,5}))
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assert(!g(S{3,5}, S{4,6}))
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assert(k(3, struct{a, b int}{3, 3}))
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assert(!k(3, struct{a, b int}{3, 4}))
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}
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func assert(b bool) {
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if !b {
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panic("assertion failed")
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}
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}
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