Add CondLink

Fix include path

opencog/atoms/execution/CMakeLists.txt

@@ -14,6 +14,7 @@ ADD_LIBRARY (execution
 	Instantiator.cc
 	MapLink.cc
 	LibraryManager.cc
+	CondLink.cc
 )
 
 # Without this, parallel make will race and crap up the generated files.
@@ -54,5 +55,6 @@ ENDIF (HAVE_GUILE)
 # are fixed, first.
 INSTALL (FILES
 	MapLink.h
+	CondLink.h
 	DESTINATION "include/opencog/atoms/core"
 )

opencog/atoms/execution/CondLink.cc

@@ -0,0 +1,72 @@
+/*
+ * opencog/atoms/execution/CondLink.cc
+ *
+ * Copyright (C) 2019 Kasim Ebrahim
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License v3 as
+ * published by the Free Software Foundation and including the
+ * exceptions at http://opencog.org/wiki/Licenses
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program; if not, write to:
+ * Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <opencog/atoms/base/ClassServer.h>
+#include <opencog/atoms/execution/Instantiator.h>
+#include <opencog/atoms/core/FindUtils.h>
+
+#include "CondLink.h"
+#include "EvaluationLink.h"
+
+using namespace opencog;
+
+void CondLink::init(void)
+{
+	if (0 == _outgoing.size())
+		throw SyntaxException(TRACE_INFO,
+		                      "CondLink is expected to be arity greater-than 0!");
+
+	if (1 == _outgoing.size()) {
+		def_exp = _outgoing[0];
+		return;
+	}
+
+	for (unsigned i = 0; i < _outgoing.size(); ++i) {
+		if (i % 2 == 0) {
+			if (i == _outgoing.size() - 1) {
+				def_exp = _outgoing[i];
+				return;
+			}
+			conds.push_back(_outgoing[i]);
+		} else {
+			exps.push_back(_outgoing[i]);
+		}
+	}
+}
+
+CondLink::CondLink(const HandleSeq &oset, Type t)
+		: FunctionLink(oset, t)
+{
+	if (not nameserver().isA(t, COND_LINK)) {
+		const std::string &tname = nameserver().getTypeName(t);
+		throw SyntaxException(TRACE_INFO,
+		                      "Expecting a CondLink, got %s", tname.c_str());
+	}
+
+	// Derived types have a different initialization sequence.
+	if (COND_LINK != t) return;
+	init();
+}
+
+Handle CondLink::execute(AtomSpace *scratch) const
+{}
+
+DEFINE_LINK_FACTORY(CondLink, COND_LINK)

opencog/atoms/execution/CondLink.h

@@ -0,0 +1,60 @@
+/*
+ * opencog/atoms/execution/CondLink.h
+ *
+ * Copyright (C) 2019 Kasim Ebrahim
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License v3 as
+ * published by the Free Software Foundation and including the exceptions
+ * at http://opencog.org/wiki/Licenses
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program; if not, write to:
+ * Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef _OPENCOG_COND_LINK_H
+#define _OPENCOG_COND_LINK_H
+
+#include <opencog/atoms/core/FunctionLink.h>
+#include <opencog/atoms/core/ScopeLink.h>
+#include <opencog/atoms/core/Quotation.h>
+
+namespace opencog
+{
+class CondLink : public FunctionLink
+{
+protected:
+	HandleSeq conds;
+	HandleSeq exps;
+	Handle def_exp;
+
+	void init(void);
+
+public:
+	CondLink(const HandleSeq&, Type=COND_LINK);
+
+	virtual Handle execute(AtomSpace* = nullptr) const;
+
+	static Handle factory(const Handle&);
+};
+
+typedef std::shared_ptr<CondLink> CondLinkPtr;
+static inline CondLinkPtr CondLinkCast(const Handle& h)
+	{ AtomPtr a(h); return std::dynamic_pointer_cast<CondLink>(a); }
+static inline CondLinkPtr CondLinkCast(AtomPtr a)
+	{ return std::dynamic_pointer_cast<CondLink>(a); }
+
+#define createCondLink std::make_shared<CondLink>
+
+/** @}*/
+}
+
+#endif // _OPENCOG_COND_LINK_H