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// RUN: %dafny /dprint:- /env:0 "%s" > "%t"
// RUN: %diff "%s.expect" "%t"
predicate P(n: int)
predicate R(r: real)
method M0()
{
if x :| P(x) {
var y := x + 3;
var x := true; // error: 'x' is already declared in this scope
}
}
method M1()
{
if x: int :| P(x) {
x := x + 1; // error: 'x' is an immutable variable
}
}
method M2()
{
var x := true;
if x, y :| P(x) && R(y) { // this declares a new 'x'
var z := x + 12;
}
x := x && false;
}
method M3()
{
var x := true;
if x: int, y :| P(x) && R(y) {
var z := x + int(y);
var w := real(x) + y;
}
var x := 0.0; // error: 'x' is already declared in this scope
}
method M4()
{
if x, y: real :| P(x) && R(y) {
}
}
method M5()
{
if x: int, y: real :| P(x) && R(y) {
}
}
method M6()
{
if x {:myattribute x, "hello"} :| P(x) {
}
if x, y {:myattribute y, "sveika"} :| P(x) && R(y) {
}
if x: int {:myattribute x, "chello"} :| P(x) {
}
if x {:myattribute x, "hola"} {:yourattribute x + x, "hej"} :| P(x) {
}
}
method M7()
{
if x :| P(x) {
} else if * {
} else if y :| R(y) {
} else if y :| P(y) {
}
}
method P0(m: int, n: int)
requires m < n
{
var x := true;
if {
case x :| P(x) =>
var t := 3 * x;
case x: int :| P(x) =>
case x, y :| P(x) && R(y) =>
y := y + 1.0; // error: 'y' is an immutable variable
case x: int, y :| P(x) && R(y) =>
case m < n =>
x := x || m + 5 == n;
case x, y: real :| P(x) && R(y) =>
case x: int, y: real :| P(x) && R(y) =>
}
assert x;
}
method P1(m: int, n: int)
requires m < n
{
if {
case x {:myattribute x, "hello"} :| P(x) =>
case x, y {:myattribute y, "sveika"} :| P(x) && R(y) =>
case x: int {:myattribute x, "chello"} :| P(x) =>
case x {:myattribute x, "hola"} {:yourattribute x + x, "hej"} :| P(x) =>
case m < n =>
}
}
module TypesNotFullyDetermined {
method T0()
{
if x :| true { // error: type not entirely resolved
}
}
method T1()
{
if x :| true {
var y := x + 3;
}
}
}
module Ghost {
predicate P(x: int) // note, P is ghost
predicate method R(x: int)
method M7() returns (z: int, b: bool)
{
if * {
z := z + -z;
} else if y :| 1000 <= y < 2000 && R(y) {
z := y;
} else if y :| 0 <= y < 100 && P(y) {
z := y; // error: not allowed, because the P in the guard makes this a ghost context
} else if y :| 0 <= y < 100 && R(y) {
z := y; // error: this is also in a ghost context, because it depends on the P above
}
if * {
z := z + -z;
} else if exists y :: 1000 <= y < 2000 && R(y) {
z := 0;
} else if exists y :: 0 <= y < 100 && P(y) {
z := 0; // error: not allowed, because the P in the guard makes this a ghost context
} else if exists y :: 0 <= y < 100 && R(y) {
z := 0; // error: this is also in a ghost context, because it depends on the P above
}
if P(z) {
z := 20; // error: blatant ghost context
}
b := exists y :: 0 <= y < 100 && P(y); // error: assignment to non-ghost of something that depends on ghost
ghost var c;
c := exists y :: 0 <= y < 100 && P(y);
b := exists y {:myattribute P(y)} :: 0 <= y < 100;
}
}
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