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cf4b6dc48e
When converting from a type param to an interface, allow it if
the type bound implements that interface.
Query: some conversions go through this path, some use another path?
The test does
var i interface{foo()int} = x
but
i := (interface{foo()int})(x)
works at tip.
Change-Id: I84d497e5228c0e1d1c9d76ffebaedce09dc45e8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/325409
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>
59 lines
1.1 KiB
Go
59 lines
1.1 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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// Test that we can convert type parameters to both empty
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// and nonempty interfaces, and named and nonnamed versions
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// thereof.
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package main
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import "fmt"
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type E interface{}
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func f[T any](x T) interface{} {
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var i interface{} = x
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return i
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}
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func g[T any](x T) E {
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var i E = x
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return i
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}
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type C interface {
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foo() int
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}
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type myInt int
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func (x myInt) foo() int {
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return int(x+1)
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}
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func h[T C](x T) interface{foo() int} {
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var i interface{foo()int} = x
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return i
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}
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func i[T C](x T) C {
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var i C = x
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return i
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}
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func main() {
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if got, want := f[int](7), 7; got != want {
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panic(fmt.Sprintf("got %d want %d", got, want))
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}
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if got, want := g[int](7), 7; got != want {
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panic(fmt.Sprintf("got %d want %d", got, want))
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}
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if got, want := h[myInt](7).foo(), 8; got != want {
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panic(fmt.Sprintf("got %d want %d", got, want))
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}
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if got, want := i[myInt](7).foo(), 8; got != want {
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panic(fmt.Sprintf("got %d want %d", got, want))
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}
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}
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