1 files changed, 53 insertions, 2 deletions
diff --git a/starts/meaning-vm/helpers.cpp b/starts/meaning-vm/helpers.cpp
index fb17f6c..99c83dd 100644
--- a/starts/meaning-vm/helpers.cpp
+++ b/starts/meaning-vm/helpers.cpp
@@ -2,10 +2,35 @@
 
 #include <unordered_map>
 
-// these concept names are for bootstrapping convenience,
+ref operator-(ref a, ref b)
+{
+	return ref(a.name() + "-" + b.name());
+}
+
+concept ref::operator=(ref other)
+{
+	// if this is link-type, make new concept
+	concept ret;
+	ret.link(*this, other);
+	return ret;
+}
+
+ref ref::operator[](concept links) {
+	ptr->links.insert(links.links.begin(), links.links.end());
+	return *this;
+}
+
+concept operator,(concept a, concept b)
+{
+	concept ret;
+	ret.links.insert(a.links.begin(), a.links.end());
+	ret.links.insert(b.links.begin(), b.links.end());
+	return ret;
+}
+
+// concept names are for bootstrapping convenience,
 // to make hardcoding structures easier.
 // hence there is just one single list of them
-
 concept namesByConcept;
 std::unordered_map<value<std::string>,concept,std::hash<std::string>> conceptsByName;
 
@@ -30,3 +55,29 @@ value<std::string> & ref::name() const
 ref::operator const char *() const {
 	return name().c_str();
 }
+
+ref a(ref what)
+{
+	static unsigned long long gid = 0;
+	declrefs(is);
+	return ref(what.name() + "-" + std::to_string(gid++))[is = what];
+}
+ref an(ref what)
+{
+	return a(what);
+}
+
+bool ref::isa(ref what) const
+{
+	declrefs(is);
+	for (auto group : ptr->getAll(is)) {
+		if (group == what) return true;
+		if (group.isa(what)) return true;
+	}
+	return false;
+}
+
+bool ref::isan(ref what) const
+{
+	return isa(what);
+}