1// compile
2
3// Copyright 2011 The Go Authors.  All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7// Test legal shifts.
8// Issue 1708, legal cases.
9// Compiles but does not run.
10
11package p
12
13func f(x int) int         { return 0 }
14func g(x interface{}) int { return 0 }
15func h(x float64) int     { return 0 }
16
17// from the spec
18var (
19	s uint  = 33
20	i       = 1 << s         // 1 has type int
21	j int32 = 1 << s         // 1 has type int32; j == 0
22	k       = uint64(1 << s) // 1 has type uint64; k == 1<<33
23	l       = g(1 << s)      // 1 has type int
24	m int   = 1.0 << s       // legal: 1.0 has type int
25	w int64 = 1.0 << 33      // legal: 1.0<<33 is a constant shift expression
26)
27
28// non-constant shift expressions
29var (
30	a1 int = 2.0 << s    // typeof(2.0) is int in this context => legal shift
31	d1     = f(2.0 << s) // typeof(2.0) is int in this context => legal shift
32)
33
34// constant shift expressions
35const c uint = 5
36
37var (
38	a2 int     = 2.0 << c    // a2 == 64 (type int)
39	b2         = 2.0 << c    // b2 == 64 (untyped integer)
40	_          = f(b2)       // verify b2 has type int
41	c2 float64 = 2 << c      // c2 == 64.0 (type float64)
42	d2         = f(2.0 << c) // == f(64)
43	e2         = g(2.0 << c) // == g(int(64))
44	f2         = h(2 << c)   // == h(float64(64.0))
45)
46