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	diff --git a/util/parameter.h b/util/parameter.h
	new file mode 100644
	index 00000000..bc04ba4b
	--- /dev/null
	+++ b/util/parameter.h
	@@ -0,0 +1,63 @@
	+#ifndef _paintown_parameter_h
	+#define _paintown_parameter_h
	+
	+/* parameters are to be used to control the dynamic extent of values. values
	+ * can be pushed onto the current extent and are automatically popped off
	+ * upon function return.
	+ * this is similar to 'parameters' in Racket.
	+ *
	+ * This class is not thread safe.
	+ */
	+
	+#include <vector>
	+
	+namespace Util{
	+
	+/* the static variable `stack' has to be defined somewhere. use this syntax to define it
	+ * template <> vector<int> Parameter<int>::stack;
	+ */
	+template <class Value>
	+class Parameter{
	+public:
	+ /* push a new value on the stack */
	+ Parameter(const Value & what):
	+ items(0){
	+ push(what);
	+ }
	+
	+ Parameter():
	+ items(0){
	+ }
	+
	+ /* pop last value */
	+ ~Parameter(){
	+ for (int i = 0; i < items; i++){
	+ if (stack.size() > 0){
	+ stack.pop_back();
	+ }
	+ }
	+ }
	+
	+ void push(const Value & what){
	+ items += 1;
	+ stack.push_back(what);
	+ }
	+
	+ /* get the current value */
	+ static Value current(){
	+ if (stack.size() > 0){
	+ return stack.back();
	+ }
	+ return Value();
	+ }
	+
	+ static std::vector<Value> stack;
	+
	+protected:
	+ /* number of things pushed onto the stack by this object */
	+ int items;
	+};
	+
	+}
	+
	+#endif