mirror of
https://github.com/golang/go
synced 2024-11-26 23:01:23 -07:00
45 lines
1.3 KiB
Go
45 lines
1.3 KiB
Go
// compile
|
|
|
|
// Copyright 2011 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 legal shifts.
|
|
// Issue 1708, legal cases.
|
|
// Compiles but does not run.
|
|
|
|
package p
|
|
|
|
func f(x int) int { return 0 }
|
|
func g(x interface{}) int { return 0 }
|
|
func h(x float64) int { return 0 }
|
|
|
|
// from the spec
|
|
var (
|
|
s uint = 33
|
|
i = 1 << s // 1 has type int
|
|
j int32 = 1 << s // 1 has type int32; j == 0
|
|
k = uint64(1 << s) // 1 has type uint64; k == 1<<33
|
|
m int = 1.0 << s // legal: 1.0 has type int
|
|
w int64 = 1.0 << 33 // legal: 1.0<<33 is a constant shift expression
|
|
)
|
|
|
|
// non-constant shift expressions
|
|
var (
|
|
a1 int = 2.0 << s // typeof(2.0) is int in this context => legal shift
|
|
d1 = f(2.0 << s) // typeof(2.0) is int in this context => legal shift
|
|
)
|
|
|
|
// constant shift expressions
|
|
const c uint = 5
|
|
|
|
var (
|
|
a2 int = 2.0 << c // a2 == 64 (type int)
|
|
b2 = 2.0 << c // b2 == 64 (untyped integer)
|
|
_ = f(b2) // verify b2 has type int
|
|
c2 float64 = 2 << c // c2 == 64.0 (type float64)
|
|
d2 = f(2.0 << c) // == f(64)
|
|
e2 = g(2.0 << c) // == g(int(64))
|
|
f2 = h(2 << c) // == h(float64(64.0))
|
|
)
|