print("=== Type System Demo ===");
print("");

print("--- Dynamic Typing ---");
x = 42;
print("x =", x, "type:", typeof(x));

x = "hello";
print("x =", x, "type:", typeof(x));

x = {1, 2, 3};
print("x = array, type:", typeof(x));

x = null;
print("x =", x, "type:", typeof(x));

print("");
print("--- Null Defaults ---");
undeclared = null;
print("null variable:", undeclared);

intDefault = int(null);
print("int(null) =", intDefault);

strDefault = str(null);
print("str(null) = \"" + strDefault + "\"");

boolDefault = bool(null);
print("bool(null) =", boolDefault);

print("");
print("--- Type Constructors ---");
fromStr = int("123");
print("int(\"123\") =", fromStr, "type:", typeof(fromStr));

fromInt = str(456);
print("str(456) =", fromInt, "type:", typeof(fromInt));

fromFloat = int(3.14);
print("int(3.14) =", fromFloat);

print("");
print("--- Type Coercion ---");
a = "The answer is: ";
b = 42;
result = a + str(b);
print(result);

c = "10";
d = int(c) + 5;
print("\"10\" + 5 =", d);

print("");
print("--- Boolean Context ---");
print("Boolean evaluation (0 = false, nonzero = true):");

values = {0, 1, -1, 42, "", "hello"};
names = {"0", "1", "-1", "42", "\"\"", "\"hello\""};

for (i = 0; i < len(values); i++) {
    if (values[i]) {
        print(names[i], "-> truthy");
    } else {
        print(names[i], "-> falsy");
    }
}

print("");
print("--- Integer as Boolean ---");
flag = 1;
if (flag) {
    print("flag (1) is truthy");
}

flag = 0;
if (flag) {
    print("This won't print");
} else {
    print("flag (0) is falsy");
}

print("");
print("--- Type Checking with typeof ---");
checkTypes = {42, "text", null};
typeNames = {"integer", "string", "null"};
for (i = 0; i < len(checkTypes); i++) {
    print(typeNames[i], "->", typeof(checkTypes[i]));
}

class TestClass {
    value = 0;
    TestClass(this) {
    }
}
obj = new TestClass();
print("object -> type:", typeof(obj));

print("");
print("--- Automatic Initialization ---");
class DefaultValues {
    intVal = 0;
    strVal = "";
    boolVal = 0;
    nullVal = null;

    DefaultValues(this) {
    }

    showDefaults(this) {
        print("intVal:", this.intVal);
        print("strVal: \"" + this.strVal + "\"");
        print("boolVal:", this.boolVal);
        print("nullVal:", this.nullVal);
    }
}

defaults = new DefaultValues();
defaults.showDefaults();