1 files changed, 97 insertions, 0 deletions
diff --git a/src/object_filter.hpp b/src/object_filter.hpp
new file mode 100644
index 00000000..469b1fa6
--- /dev/null
+++ b/src/object_filter.hpp
@@ -0,0 +1,97 @@
+#pragma once
+
+#include "angband.h"
+#include <functional>
+#include <initializer_list>
+
+typedef std::function<bool (object_type const *)> object_filter_t;
+
+namespace object_filter {
+
+/**
+ * Is TVal equal to the given value?
+ */
+object_filter_t TVal(byte tval);
+
+/**
+ * Is SVal equal to the given value?
+ */
+object_filter_t SVal(byte sval);
+
+/**
+ * Has given bit mask in flag3 value.
+ */
+object_filter_t HasFlag3(u32b mask);
+
+/**
+ * Has given bit mask in flag4 value.
+ */
+object_filter_t HasFlag4(u32b mask);
+
+/**
+ * Has given bit mask in flag5 value.
+ */
+object_filter_t HasFlag5(u32b mask);
+
+/**
+ * Is the object an artifact?
+ */
+object_filter_t IsArtifact();
+
+/**
+ * Is the object an artifact as determined by artifact_p?
+ */
+object_filter_t IsArtifactP();
+
+/**
+ * Is the object an ego item?
+ */
+object_filter_t IsEgo();
+
+/**
+ * Is the object "known"?
+ */
+object_filter_t IsKnown();
+
+/**
+ * True always accepts all items.
+ */
+object_filter_t True();
+
+/**
+ * Invert an object filter.
+ */
+object_filter_t Not(object_filter_t p);
+
+/**
+ * Logical conjunction (AND)
+ */
+object_filter_t And();
+
+/**
+ * Logical conjunction (AND)
+ */
+template<typename Arg0, typename... Args> object_filter_t And(Arg0&& arg0, Args&&... args) {
+	auto argsFilter = And(args...);
+	return [=](object_type const *o_ptr) -> bool {
+		return arg0(o_ptr) && argsFilter(o_ptr);
+	};
+}
+
+/**
+ * Logical disjunction (OR)
+ */
+object_filter_t Or();
+
+/**
+ * Logical disjunction (OR)
+ */
+template<typename Arg0, typename... Args> object_filter_t Or(Arg0&& arg0, Args&&... args) {
+	auto argsFilter = Or(args...);
+	return [=](object_type const *o_ptr) -> bool {
+		auto x = arg0(o_ptr) || argsFilter(o_ptr);
+		return x;
+	};
+}
+
+}