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// compile
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Test iota inside a function in a ConstSpec is accepted
package main
import (
"unsafe"
)
// iotas are usable inside closures in constant declarations (#22345)
const (
_ = iota
_ = len([iota]byte{})
_ = unsafe.Sizeof(iota)
_ = unsafe.Sizeof(func() { _ = iota })
_ = unsafe.Sizeof(func() { var _ = iota })
_ = unsafe.Sizeof(func() { const _ = iota })
_ = unsafe.Sizeof(func() { type _ [iota]byte })
_ = unsafe.Sizeof(func() { func() int { return iota }() })
)
// verify inner and outer const declarations have distinct iotas
const (
zero = iota
one = iota
_ = unsafe.Sizeof(func() {
var x [iota]int // [2]int
var y [iota]int // [2]int
const (
Zero = iota
One
Two
_ = unsafe.Sizeof([iota - 1]int{} == x) // assert types are equal
_ = unsafe.Sizeof([iota - 2]int{} == y) // assert types are equal
_ = unsafe.Sizeof([Two]int{} == x) // assert types are equal
)
var z [iota]int // [2]int
_ = unsafe.Sizeof([2]int{} == z) // assert types are equal
})
three = iota // the sequence continues
)
var _ [three]int = [3]int{} // assert 'three' has correct value
func main() {
const (
_ = iota
_ = len([iota]byte{})
_ = unsafe.Sizeof(iota)
_ = unsafe.Sizeof(func() { _ = iota })
_ = unsafe.Sizeof(func() { var _ = iota })
_ = unsafe.Sizeof(func() { const _ = iota })
_ = unsafe.Sizeof(func() { type _ [iota]byte })
_ = unsafe.Sizeof(func() { func() int { return iota }() })
)
const (
zero = iota
one = iota
_ = unsafe.Sizeof(func() {
var x [iota]int // [2]int
var y [iota]int // [2]int
const (
Zero = iota
One
Two
_ = unsafe.Sizeof([iota - 1]int{} == x) // assert types are equal
_ = unsafe.Sizeof([iota - 2]int{} == y) // assert types are equal
_ = unsafe.Sizeof([Two]int{} == x) // assert types are equal
)
var z [iota]int // [2]int
_ = unsafe.Sizeof([2]int{} == z) // assert types are equal
})
three = iota // the sequence continues
)
var _ [three]int = [3]int{} // assert 'three' has correct value
}
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