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![Dan Scales](/assets/img/avatar_default.png)
We need an extra case in convertToDictionary. In the case of an operand which is an interface and converting to an empty interface, we don't want to get the run-time type from the dictionary (which would be the run-time type of the interface). We want to do a type-assert to the empty interface. Change-Id: I414247210168153151272fab198bfe82ad7b1567 Reviewed-on: https://go-review.googlesource.com/c/go/+/342009 Run-TryBot: Dan Scales <danscales@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org> Trust: Dan Scales <danscales@google.com>
56 lines
1.1 KiB
Go
56 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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package main
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import (
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"errors"
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"fmt"
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)
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type Option[T any] struct {
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ok bool
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val T
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}
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func (o Option[T]) String() string {
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if o.ok {
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return fmt.Sprintf("Some(%v)", o.val)
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}
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return "None"
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}
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func Some[T any](val T) Option[T] { return Option[T]{ok: true, val: val} }
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func None[T any]() Option[T] { return Option[T]{ok: false} }
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type Result[T, E any] struct {
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ok bool
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val T
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err E
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}
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func (r Result[T, E]) String() string {
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if r.ok {
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return fmt.Sprintf("Ok(%v)", r.val)
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}
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return fmt.Sprintf("Err(%v)", r.err)
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}
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func Ok[T, E any](val T) Result[T, E] { return Result[T, E]{ok: true, val: val} }
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func Err[T, E any](err E) Result[T, E] { return Result[T, E]{ok: false, err: err} }
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func main() {
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a := Some[int](1)
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b := None[int]()
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fmt.Println(a, b)
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x := Ok[int, error](1)
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y := Err[int, error](errors.New("test"))
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fmt.Println(x, y)
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// fmt.Println(x)
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_, _, _, _ = a, b, x, y
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}
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