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// 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
l = g(1 << s) // 1 has type int
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))
)
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