implement move checking furthermvcheck

+ Enough that examples still compile, but missing references etc.

4 files changed, 32 insertions, 9 deletions

diff --git a/examples/fib.fwd b/examples/fib.fwd
index be2b63f..e5014af 100644
--- a/examples/fib.fwd
+++ b/examples/fib.fwd
@@ -5,17 +5,19 @@
 
 fib(int n, (int) res)
 {
-	if n < 2 {
+	fwd_copy(n) => int n1, int n2;
+	if n1 < 2 {
 		res(1);
 	} else {
-		fib(n - 1) => int f1;
-		fib(n - 2) => int f2;
+		fib(n2 - 1) => int f1;
+		fib(n2 - 2) => int f2;
 		res(f1 + f2);
 	}
 }
 
 /* 'extern' println */
-fwd_println(int n);
+fwd_println(auto n);
+fwd_copy(auto n, (auto, auto) n1);
 
 main()
 {
diff --git a/examples/guard.fwd b/examples/guard.fwd
index cf9578e..df42ef3 100644
--- a/examples/guard.fwd
+++ b/examples/guard.fwd
@@ -2,6 +2,12 @@
  * eventually be replaced but this is good enough to play around with */
 fwd_println(auto s);
 
+/* this is a hack, just creates two copies of whatever is passed to it.
+ * Primitive types should probably be excluded from the move checking, and more
+ * complex types would presumably implement some kind of .copy(), but at the
+ * moment that's still TODO */
+fwd_copy(auto n, (auto, auto) n1);
+
 guard(bool cond, () err, () ok)
 {
 	if cond {
@@ -13,15 +19,17 @@ guard(bool cond, () err, () ok)
 
 try_print_one(int a)
 {
-	guard(a < 1) => {
+	fwd_copy(a) => int a1, int a2;
+	guard(a1 < 1) => {
 		fwd_println("smaller than 1");
 	} => ;
 
-	guard(a > 1) => {
+	fwd_copy(a2) => int a3, int a4;
+	guard(a3 > 1) => {
 		fwd_println("larger than 1");
 	} => ;
 
-	fwd_println(a);
+	fwd_println(a4);
 }
 
 main()
diff --git a/examples/opt_group.fwd b/examples/opt_group.fwd
new file mode 100644
index 0000000..e520c70
--- /dev/null
+++ b/examples/opt_group.fwd
@@ -0,0 +1,14 @@
+do_something(() a | () b)
+{
+	a();
+
+	/* should fail, since either a or b should be called, but not both */
+	b();
+}
+
+main()
+{
+	do_something()
+	=> {}
+	=> {}
+}
diff --git a/examples/uniq.fwd b/examples/uniq.fwd
index 9eb0092..c1edc1b 100644
--- a/examples/uniq.fwd
+++ b/examples/uniq.fwd
@@ -5,8 +5,7 @@ fwd_getline(
 	(optional![string]) next);
 
 fwd_some(optional![string] o,
-	(string) something,
-	() nothing);
+	(string) something | () nothing);
 
 fwd_insert(unordered_set![string] set, string line,
 	(unordered_set![string]) next);