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Diffstat (limited to 'Source/Jennisys/examples/mod2/jennisys-synth_NumberMethods.dfy')
-rw-r--r--Source/Jennisys/examples/mod2/jennisys-synth_NumberMethods.dfy167
1 files changed, 167 insertions, 0 deletions
diff --git a/Source/Jennisys/examples/mod2/jennisys-synth_NumberMethods.dfy b/Source/Jennisys/examples/mod2/jennisys-synth_NumberMethods.dfy
new file mode 100644
index 00000000..b20e2741
--- /dev/null
+++ b/Source/Jennisys/examples/mod2/jennisys-synth_NumberMethods.dfy
@@ -0,0 +1,167 @@
+class NumberMethods {
+ ghost var Repr: set<object>;
+
+
+ function Valid_repr(): bool
+ reads *;
+ {
+ this in Repr &&
+ null !in Repr
+ }
+
+ function Valid_self(): bool
+ reads *;
+ {
+ Valid_repr() &&
+ true
+ }
+
+ function Valid(): bool
+ reads *;
+ {
+ this.Valid_self() &&
+ true
+ }
+
+
+ method Abs(a: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a, -a};
+ ensures ret >= 0;
+ {
+ if (-a >= 0) {
+ ret := -a;
+ } else {
+ ret := a;
+ }
+ }
+
+
+ method Double(p: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret == 2 * p;
+ {
+ ret := 2 * p;
+ }
+
+
+ method Min2(a: int, b: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures a < b ==> ret == a;
+ ensures a >= b ==> ret == b;
+ {
+ if (a < b) {
+ ret := a;
+ } else {
+ ret := b;
+ }
+ }
+
+
+ method Min22(a: int, b: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a, b};
+ ensures ret <= a;
+ ensures ret <= b;
+ {
+ if (a <= b) {
+ ret := a;
+ } else {
+ ret := b;
+ }
+ }
+
+
+ method Min3(a: int, b: int, c: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a, b, c};
+ ensures ret <= a;
+ ensures ret <= b;
+ ensures ret <= c;
+ {
+ ret := this.Min32(a, b, c);
+ }
+
+
+ method Min32(a: int, b: int, c: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a, b, c};
+ ensures ret <= a;
+ ensures ret <= b;
+ ensures ret <= c;
+ {
+ if (a <= b && a <= c) {
+ ret := a;
+ } else {
+ if (c <= a && c <= b) {
+ ret := c;
+ } else {
+ ret := b;
+ }
+ }
+ }
+
+
+ method Min4(a: int, b: int, c: int, d: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a, b, c, d};
+ ensures ret <= a;
+ ensures ret <= b;
+ ensures ret <= c;
+ ensures ret <= d;
+ {
+ if ((a <= b && a <= c) && a <= d) {
+ ret := a;
+ } else {
+ if ((d <= a && d <= b) && d <= c) {
+ ret := d;
+ } else {
+ if ((c <= a && c <= b) && c <= d) {
+ ret := c;
+ } else {
+ ret := b;
+ }
+ }
+ }
+ }
+
+
+ method MinSum(a: int, b: int, c: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret in {a + b, a + c, b + c};
+ ensures ret <= a + b;
+ ensures ret <= b + c;
+ ensures ret <= a + c;
+ {
+ ret := this.Min3(a + b, b + c, a + c);
+ }
+
+
+ method Sum(a: int, b: int) returns (ret: int)
+ requires Valid();
+ ensures fresh(Repr - old(Repr));
+ ensures Valid();
+ ensures ret == a + b;
+ {
+ ret := a + b;
+ }
+
+}
+
+