1 // run 2 3 // Copyright 2009 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 simple boolean and numeric constants. 8 9 package main 10 11 import "os" 12 13 const ( 14 c0 = 0 15 cm1 = -1 16 chuge = 1 << 100 17 chuge_1 = chuge - 1 18 c1 = chuge >> 100 19 c3div2 = 3 / 2 20 c1e3 = 1e3 21 22 rsh1 = 1e100 >> 1000 23 rsh2 = 1e302 >> 1000 24 25 ctrue = true 26 cfalse = !ctrue 27 ) 28 29 const ( 30 f0 = 0.0 31 fm1 = -1. 32 fhuge float64 = 1 << 100 33 fhuge_1 float64 = chuge - 1 34 f1 float64 = chuge >> 100 35 f3div2 = 3. / 2. 36 f1e3 float64 = 1e3 37 ) 38 39 func assert(t bool, s string) { 40 if !t { 41 panic(s) 42 } 43 } 44 45 func ints() { 46 assert(c0 == 0, "c0") 47 assert(c1 == 1, "c1") 48 assert(chuge > chuge_1, "chuge") 49 assert(chuge_1+1 == chuge, "chuge 1") 50 assert(chuge+cm1+1 == chuge, "cm1") 51 assert(c3div2 == 1, "3/2") 52 assert(c1e3 == 1000, "c1e3 int") 53 assert(c1e3 == 1e3, "c1e3 float") 54 assert(rsh1 == 0, "rsh1") 55 assert(rsh2 == 9, "rsh2") 56 57 // verify that all (in range) are assignable as ints 58 var i int 59 i = c0 60 assert(i == c0, "i == c0") 61 i = cm1 62 assert(i == cm1, "i == cm1") 63 i = c1 64 assert(i == c1, "i == c1") 65 i = c3div2 66 assert(i == c3div2, "i == c3div2") 67 i = c1e3 68 assert(i == c1e3, "i == c1e3") 69 70 // verify that all are assignable as floats 71 var f float64 72 f = c0 73 assert(f == c0, "f == c0") 74 f = cm1 75 assert(f == cm1, "f == cm1") 76 f = chuge 77 assert(f == chuge, "f == chuge") 78 f = chuge_1 79 assert(f == chuge_1, "f == chuge_1") 80 f = c1 81 assert(f == c1, "f == c1") 82 f = c3div2 83 assert(f == c3div2, "f == c3div2") 84 f = c1e3 85 assert(f == c1e3, "f == c1e3") 86 } 87 88 func floats() { 89 assert(f0 == c0, "f0") 90 assert(f1 == c1, "f1") 91 // TODO(gri): exp/ssa/interp constant folding is incorrect. 92 if os.Getenv("GOSSAINTERP") == "" { 93 assert(fhuge == fhuge_1, "fhuge") // float64 can't distinguish fhuge, fhuge_1. 94 } 95 assert(fhuge_1+1 == fhuge, "fhuge 1") 96 assert(fhuge+fm1+1 == fhuge, "fm1") 97 assert(f3div2 == 1.5, "3./2.") 98 assert(f1e3 == 1000, "f1e3 int") 99 assert(f1e3 == 1.e3, "f1e3 float") 100 101 // verify that all (in range) are assignable as ints 102 var i int 103 i = f0 104 assert(i == f0, "i == f0") 105 i = fm1 106 assert(i == fm1, "i == fm1") 107 108 // verify that all are assignable as floats 109 var f float64 110 f = f0 111 assert(f == f0, "f == f0") 112 f = fm1 113 assert(f == fm1, "f == fm1") 114 f = fhuge 115 assert(f == fhuge, "f == fhuge") 116 f = fhuge_1 117 assert(f == fhuge_1, "f == fhuge_1") 118 f = f1 119 assert(f == f1, "f == f1") 120 f = f3div2 121 assert(f == f3div2, "f == f3div2") 122 f = f1e3 123 assert(f == f1e3, "f == f1e3") 124 } 125 126 func interfaces() { 127 var ( 128 nilN interface{} 129 nilI *int 130 five = 5 131 132 _ = nil == interface{}(nil) 133 _ = interface{}(nil) == nil 134 ) 135 ii := func(i1 interface{}, i2 interface{}) bool { return i1 == i2 } 136 ni := func(n interface{}, i int) bool { return n == i } 137 in := func(i int, n interface{}) bool { return i == n } 138 pi := func(p *int, i interface{}) bool { return p == i } 139 ip := func(i interface{}, p *int) bool { return i == p } 140 141 assert((interface{}(nil) == interface{}(nil)) == ii(nilN, nilN), 142 "for interface{}==interface{} compiler == runtime") 143 144 assert(((*int)(nil) == interface{}(nil)) == pi(nilI, nilN), 145 "for *int==interface{} compiler == runtime") 146 assert((interface{}(nil) == (*int)(nil)) == ip(nilN, nilI), 147 "for interface{}==*int compiler == runtime") 148 149 assert((&five == interface{}(nil)) == pi(&five, nilN), 150 "for interface{}==*int compiler == runtime") 151 assert((interface{}(nil) == &five) == ip(nilN, &five), 152 "for interface{}==*int compiler == runtime") 153 154 assert((5 == interface{}(5)) == ni(five, five), 155 "for int==interface{} compiler == runtime") 156 assert((interface{}(5) == 5) == in(five, five), 157 "for interface{}==int comipiler == runtime") 158 } 159 160 func main() { 161 ints() 162 floats() 163 interfaces() 164 165 assert(ctrue == true, "ctrue == true") 166 assert(cfalse == false, "cfalse == false") 167 } 168