codekingpro/portable-devtools

1// compile2 3// Copyright 2011 The Go Authors. All rights reserved.4// Use of this source code is governed by a BSD-style5// 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 p12 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 spec18var (19	s uint  = 3320	i       = 1 << s         // 1 has type int21	j int32 = 1 << s         // 1 has type int32; j == 022	k       = uint64(1 << s) // 1 has type uint64; k == 1<<3323	l       = g(1 << s)      // 1 has type int24	m int   = 1.0 << s       // legal: 1.0 has type int25	w int64 = 1.0 << 33      // legal: 1.0<<33 is a constant shift expression26)27 28// non-constant shift expressions29var (30	a1 int = 2.0 << s    // typeof(2.0) is int in this context => legal shift31	d1     = f(2.0 << s) // typeof(2.0) is int in this context => legal shift32)33 34// constant shift expressions35const c uint = 536 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 int41	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