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// Copyright 2012 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.
// constant declarations
package const0
// constants declarations must be initialized by constants
var x = 0
const c0 = x /* ERROR "not constant" */
// untyped constants
const (
// boolean values
ub0 = false
ub1 = true
ub2 = 2 < 1
ub3 = ui1 == uf1
ub4 = true /* ERROR "cannot convert" */ == 0
// integer values
ui0 = 0
ui1 = 1
ui2 = 42
ui3 = 3141592653589793238462643383279502884197169399375105820974944592307816406286
ui4 = -10
ui5 = ui0 + ui1
ui6 = ui1 - ui1
ui7 = ui2 * ui1
ui8 = ui3 / ui3
ui9 = ui3 % ui3
ui10 = 1 / 0 /* ERROR "division by zero" */
ui11 = ui1 / 0 /* ERROR "division by zero" */
ui12 = ui3 / ui0 /* ERROR "division by zero" */
ui13 = 1 % 0 /* ERROR "division by zero" */
ui14 = ui1 % 0 /* ERROR "division by zero" */
ui15 = ui3 % ui0 /* ERROR "division by zero" */
ui16 = ui2 & ui3
ui17 = ui2 | ui3
ui18 = ui2 ^ ui3
// floating point values
uf0 = 0.
uf1 = 1.
uf2 = 4.2e1
uf3 = 3.141592653589793238462643383279502884197169399375105820974944592307816406286
uf4 = 1e-1
uf5 = uf0 + uf1
uf6 = uf1 - uf1
uf7 = uf2 * uf1
uf8 = uf3 / uf3
uf9 = uf3 /* ERROR "not defined" */ % uf3
uf10 = 1 / 0 /* ERROR "division by zero" */
uf11 = uf1 / 0 /* ERROR "division by zero" */
uf12 = uf3 / uf0 /* ERROR "division by zero" */
uf16 = uf2 /* ERROR "not defined" */ & uf3
uf17 = uf2 /* ERROR "not defined" */ | uf3
uf18 = uf2 /* ERROR "not defined" */ ^ uf3
// complex values
uc0 = 0.i
uc1 = 1.i
uc2 = 4.2e1i
uc3 = 3.141592653589793238462643383279502884197169399375105820974944592307816406286i
uc4 = 1e-1i
uc5 = uc0 + uc1
uc6 = uc1 - uc1
uc7 = uc2 * uc1
uc8 = uc3 / uc3
uc9 = uc3 /* ERROR "not defined" */ % uc3
uc10 = 1 / 0 /* ERROR "division by zero" */
uc11 = uc1 / 0 /* ERROR "division by zero" */
uc12 = uc3 / uc0 /* ERROR "division by zero" */
uc16 = uc2 /* ERROR "not defined" */ & uc3
uc17 = uc2 /* ERROR "not defined" */ | uc3
uc18 = uc2 /* ERROR "not defined" */ ^ uc3
)
type (
mybool bool
myint int
myfloat float64
mycomplex complex128
)
// typed constants
const (
// boolean values
tb0 bool = false
tb1 bool = true
tb2 mybool = 2 < 1
tb3 mybool = ti1 /* ERROR "cannot compare" */ == tf1
// integer values
ti0 int8 = ui0
ti1 int32 = ui1
ti2 int64 = ui2
ti3 myint = ui3 /* ERROR "overflows" */
ti4 myint = ui4
ti5 = ti0 /* ERROR "mismatched types" */ + ti1
ti6 = ti1 - ti1
ti7 = ti2 /* ERROR "mismatched types" */ * ti1
//ti8 = ti3 / ti3 // TODO(gri) enable this
//ti9 = ti3 % ti3 // TODO(gri) enable this
ti10 = 1 / 0 /* ERROR "division by zero" */
ti11 = ti1 / 0 /* ERROR "division by zero" */
ti12 = ti3 /* ERROR "mismatched types" */ / ti0
ti13 = 1 % 0 /* ERROR "division by zero" */
ti14 = ti1 % 0 /* ERROR "division by zero" */
ti15 = ti3 /* ERROR "mismatched types" */ % ti0
ti16 = ti2 /* ERROR "mismatched types" */ & ti3
ti17 = ti2 /* ERROR "mismatched types" */ | ti4
ti18 = ti2 ^ ti5 // no mismatched types error because the type of ti5 is unknown
// floating point values
tf0 float32 = 0.
tf1 float32 = 1.
tf2 float64 = 4.2e1
tf3 myfloat = 3.141592653589793238462643383279502884197169399375105820974944592307816406286
tf4 myfloat = 1e-1
tf5 = tf0 + tf1
tf6 = tf1 - tf1
tf7 = tf2 /* ERROR "mismatched types" */ * tf1
// tf8 = tf3 / tf3 // TODO(gri) enable this
tf9 = tf3 /* ERROR "not defined" */ % tf3
tf10 = 1 / 0 /* ERROR "division by zero" */
tf11 = tf1 / 0 /* ERROR "division by zero" */
tf12 = tf3 /* ERROR "mismatched types" */ / tf0
tf16 = tf2 /* ERROR "mismatched types" */ & tf3
tf17 = tf2 /* ERROR "mismatched types" */ | tf3
tf18 = tf2 /* ERROR "mismatched types" */ ^ tf3
// complex values
tc0 = 0.i
tc1 = 1.i
tc2 = 4.2e1i
tc3 = 3.141592653589793238462643383279502884197169399375105820974944592307816406286i
tc4 = 1e-1i
tc5 = tc0 + tc1
tc6 = tc1 - tc1
tc7 = tc2 * tc1
tc8 = tc3 / tc3
tc9 = tc3 /* ERROR "not defined" */ % tc3
tc10 = 1 / 0 /* ERROR "division by zero" */
tc11 = tc1 / 0 /* ERROR "division by zero" */
tc12 = tc3 / tc0 /* ERROR "division by zero" */
tc16 = tc2 /* ERROR "not defined" */ & tc3
tc17 = tc2 /* ERROR "not defined" */ | tc3
tc18 = tc2 /* ERROR "not defined" */ ^ tc3
)
// initialization cycles
const (
a /* ERROR "cycle" */ = a
b /* ERROR "cycle" */ , c /* ERROR "cycle" */, d, e = e, d, c, b // TODO(gri) should only have one cycle error
f float64 = d
)
// multiple initialization
const (
a1, a2, a3 = 7, 3.1415926, "foo"
b1, b2, b3 = b3, b1, 42
_p0 = assert(a1 == 7)
_p1 = assert(a2 == 3.1415926)
_p2 = assert(a3 == "foo")
_p3 = assert(b1 == 42)
_p4 = assert(b2 == 42)
_p5 = assert(b3 == 42)
)
// iota
const (
iota0 = iota
iota1 = iota
iota2 = iota*2
_a0 = assert(iota0 == 0)
_a1 = assert(iota1 == 1)
_a2 = assert(iota2 == 4)
iota6 = iota*3
iota7
iota8
_a3 = assert(iota7 == 21)
_a4 = assert(iota8 == 24)
)
const (
_b0 = iota
_b1 = assert(iota + iota2 == 5)
)
// special cases
const (
_n0 = nil /* ERROR "invalid constant type" */
_n1 = [ /* ERROR "not constant" */ ]int{}
)
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