/* Map string -> unknown */
		map<string, unknown> foo <- ["a"::1.0, "b"::1];
		write "type_of(foo[a]): " + type_of(foo["a"]); // float (OK)
		write "foo[a]: " + foo["a"]; // 1.0 (OK)
		write "foo[a] * 1.5 = " + foo["a"] * 1.5; // 1.5 (OK)
		write "type_of(foo[b]): " + type_of(foo["b"]); // int (OK)
		write "foo[b] + 1 = " + foo["b"] + 1; // 11 (?!)
		
		/* pointer copy */
		map<string, unknown> qux <- foo;
		foo["a"] <- 2.0; // since it is a pointer copy (I suppose), it also affects qux["a"] (OK)
		write "type_of(qux[a]): " + type_of(qux["a"]); // float (OK)
		write "qux[a] * 1.5 = " + qux["a"] * 1.5; // 3.0 (OK)
		write "type_of(qux[b]): " + type_of(qux["b"]); // int (OK)
		write "qux[b] + 1 = " + qux["b"] + 1; // 11 (!?) 
		
		/* Pointer copy sent to a species */
		create bar number: 1 with: [baz::foo] returns: _bar;
		bar my_bar <- first(_bar);
		foo["a"] <- 6.0; // since it is yet another pointer copy, it also affects my_bar.baz["a"] (OK)
		write "my_bar.baz[b] + 1 = " + my_bar.baz["b"] + 1; // 11 (!?)
		write "type_of(my_bar.baz['a']): " + type_of(my_bar.baz['a']); // float (OK)
		write "my_bar.baz['a']: " + my_bar.baz['a']; // 6.0 (OK)
		write "float(my_bar.baz['a']) * 1.5 = " + float(my_bar.baz["a"]) * 1.5; // 9.0 (OK)
		write "foo[a] * 1.5 = " + foo["a"] * 1.5; // 9.0 (OK) if we use the original pointer, everything is fine
		write "qux[a] * 1.5 = " + qux["a"] * 1.5; // 9.0 (OK) if we use the second pointer, everything is fine
		/* But if we use the third pointer, an error occurs;
		 * Error message;
		 * ClassCastException: class.java.lang.Double cannot be cast to class ummisco.gaml.extensions.image.GamaImage (java.lang.Double is in module.java.base of loader 'bootstrap'; ummisco.gaml.extensions.image.GamaImage is in unnamed module of loader org.eclipse.osgi.inte
		 */ 
		write "my_bar.baz['a'] * 1.5 = " + my_bar.baz["a"] * 1.5;