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// Copyright 2018, 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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package value
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import (
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	"reflect"
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	"unsafe"
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)
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// Pointer is an opaque typed pointer and is guaranteed to be comparable.
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type Pointer struct {
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	p unsafe.Pointer
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	t reflect.Type
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}
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// PointerOf returns a Pointer from v, which must be a
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// reflect.Ptr, reflect.Slice, or reflect.Map.
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func PointerOf(v reflect.Value) Pointer {
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	// The proper representation of a pointer is unsafe.Pointer,
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	// which is necessary if the GC ever uses a moving collector.
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	return Pointer{unsafe.Pointer(v.Pointer()), v.Type()}
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}
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// IsNil reports whether the pointer is nil.
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func (p Pointer) IsNil() bool {
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	return p.p == nil
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}
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// Uintptr returns the pointer as a uintptr.
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func (p Pointer) Uintptr() uintptr {
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	return uintptr(p.p)
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}
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