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// RUN: %dafny /compile:3 /spillTargetCode:2 /compileTarget:cs "%s" > "%t"
// RUN: %dafny /compile:3 /spillTargetCode:2 /compileTarget:js "%s" >> "%t"
// RUN: %dafny /compile:3 /spillTargetCode:2 /compileTarget:go "%s" >> "%t"
// RUN: %diff "%s.expect" "%t"
datatype List = Nil | Cons(head: int, tail: List)
method Main() {
var a := Nil;
var b := Cons(5, a);
var c := (a, b);
var d := (c.1, c.0);
var e := ();
print a, "\n";
print b, "\n";
print c, "\n";
print d, "\n";
print e, "\n";
print b.head, " ", b.tail, "\n";
var u := Up(0, 7);
print u, "\n";
var s := Sum(u);
PrintSum(u, "");
print " == ", s;
s := SumAgain(u);
print " (once more, that's ", s, ")\n";
CoDt();
AllBerry();
TestConflictingNames();
TestModule();
}
function method Up(m: nat, n: nat): List
requires m <= n
decreases n - m
{
if m == n then Nil else Cons(m, Up(m+1, n))
}
function method Sum(xs: List): int {
match xs // top-level match expression
case Nil => 0
case Cons(x, tail) => x + Sum(tail)
}
function method SumAgain(xs: List): int {
var r := match xs // let expression; non-top-level match expression
case Nil => 0
case Cons(x, tail) => x + SumAgain(tail);
r
}
method PrintSum(xs: List, prefix: string) {
match xs // match statement
case Nil =>
case Cons(x, tail) =>
print prefix, x;
PrintSum(tail, " + "); // tail recursion
}
method CoDt() {
var s := CoUp(0, true);
var l := ToList(s, 4);
print l, "\n";
if l.Cons? {
print l.head, " ", l.tail, "\n";
}
print s, "\n";
var s' := Next(-20, s); // not a lazy invocation
print s', "\n";
}
codatatype Stream = Next(shead: int, stail: Stream)
function method CoUp(n: int, b: bool): Stream
{
if b then
CoUp(n, false) // recursive, not co-recursive, call
else
Next(n, CoUp(n+1, true)) // CoUp is co-recursive call
}
function method ToList(s: Stream, n: nat): List
{
if n == 0 then Nil else Cons(s.shead, ToList(s.stail, n-1))
}
datatype Berry = Smultron | Jordgubb | Hjortron | Hallon
predicate method IsRed(b: Berry) {
b != Berry.Hjortron
}
codatatype CoBerry = Smultron | Jordgubb | Hjortron | Hallon // no reason for this to be a co-datatype, but, hey, why not
predicate method IsCoRed(b: CoBerry) {
b == CoBerry.Hjortron
}
method AllBerry() {
var s := set b: Berry | IsRed(b);
print s, "\n";
var c :| IsCoRed(c);
print c, " ", c.Hjortron?, " ", c == CoBerry.Hjortron, " ", c.Smultron?, "\n";
var n := Inf();
print n == Zero, "\n";
}
codatatype NatPlus = Succ(NatPlus) | Zero
function method Inf(): NatPlus {
Succ(Inf())
}
datatype ConflictingNames = ConflictingNames1(len: int, public: char, goto: string) | ConflictingNames2(goto: string)
method TestConflictingNames() {
var x := ConflictingNames1(42, 'q', "hello");
print x.len, " ", x.public, " ", x.goto, "\n";
}
module Module {
datatype OptionInt = Some(int) | None
}
method TestModule() {
PrintMaybe(Module.Some(1701));
}
method PrintMaybe(x : Module.OptionInt) {
match x
case Some(n) => print n, "\n";
case None => print "None\n";
}
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