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// verify this program with -checkLeaks -defaults -autoFold
class Client {
method Main() {
var b := new RockBand
call b.Init()
call b.Play()
call b.Play()
call b.Dispose()
}
}
class RockBand module M {
var gigs: int
var gt: Guitar
var doowops: seq<Vocalist>
var b3: Organ
predicate Valid {
acc(gigs) && 0 <= gigs &&
acc(gt) && gt != null && gt.Valid &&
acc(gt.mu) && // to enable an eventual free
acc(doowops) && //forall{d: Vocalist in doowops; d != null && d.Valid} &&
acc(b3) && b3 != null && b3.Valid &&
acc(b3.mu) // to enable an eventual free
}
method Init()
requires acc(this.*)
ensures Valid
{
gigs := 0
gt := new Guitar
call gt.Init()
b3 := new Organ
call b3.Init()
}
method Dispose()
requires Valid && acc(mu)
{
call gt.Dispose()
call b3.Dispose()
free this
}
method Play()
requires Valid
ensures Valid
{
gigs := gigs + 1
call gt.Strum()
call b3.Grind()
}
}
class Guitar module Musicians {
predicate Valid { true }
method Init()
requires acc(this.*)
ensures Valid
{
}
method Dispose()
requires Valid && acc(mu)
{
free this
}
method Strum()
requires Valid
ensures Valid
{
}
}
class Vocalist module Musicians {
predicate Valid { true }
method Init()
requires acc(this.*)
ensures Valid
{
}
method Dispose()
requires Valid && acc(mu)
{
free this
}
method Strum()
requires Valid
ensures Valid
{
}
}
class Organ module Musicians {
predicate Valid { true }
method Init()
requires acc(this.*)
ensures Valid
{
}
method Dispose()
requires Valid && acc(mu)
{
free this
}
method Grind()
requires Valid
ensures Valid
{
}
}
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