Implement "raise" function

src/error.hpp

@@ -21,6 +21,7 @@ enum class ErrorCode {
   DivisionByZero,
   SyntaxError,
   RuntimeError,
+  Raise,
 };
 
 class Value;

src/stdlib.cpp

@@ -293,6 +293,28 @@ Result<StackFrame> stdlib_error(const StackFrame& stack) {
   return ERROR_OBJ(RuntimeError, val);
 }
 
+Result<StackFrame> stdlib_raise(const StackFrame& stack) {
+  auto stack_size = TRY(stack.size());
+
+  if (stack_size > 1) {
+    auto accumulator = TRY(stack.get(0));
+    auto res = TRY(stack.set(0, accumulator));
+    res = TRY(res.ret(0));
+
+    return res;
+  }
+
+  auto params = TRY(stack.get(0));
+  auto size = TRY(params.size());
+  if (size != 1) return ERROR(ArgumentCountMismatch);
+
+  auto val = TRY(params.get(0));
+
+  auto cont = Value(TRY(Continuation::create(val, stack)));
+
+  return ERROR_OBJ(Raise, cont);
+}
+
 #define STDLIB_FUNCTION(name, id)                                  \
   [(uint64_t)StdlibFunctionId::id] = {#name, StdlibFunctionId::id, \
                                       stdlib_##name}
@@ -312,6 +334,7 @@ static StdlibFunctionEntry function_entries[] = {
     STDLIB_FUNCTION(size, Size),
     STDLIB_FUNCTION(map, Map),
     STDLIB_FUNCTION(error, Error),
+    STDLIB_FUNCTION(raise, Raise),
     [(uint64_t)StdlibFunctionId::Max] = {0, StdlibFunctionId::Max,
                                          stdlib_unknown},
 };

src/stdlib.hpp

@@ -19,6 +19,7 @@ enum class StdlibFunctionId : uint64_t {
   Size,
   Map,
   Error,
+  Raise,
   Max,
 };
 

src/valeri.cpp

@@ -18,10 +18,13 @@ Result<void> print_error(const Result<Value>& res, const String& backtrace) {
     auto errobj = TRY(geterrobj().copy());
     if (errobj.is<Nil>()) {
       debug_print(geterr());
-    } else {
+    } else if (errobj.is<Error>()) {
       auto message = TRY(errobj.to<Error>()->message());
       print_string(*message.to<String>());
       std::cout << "\n";
+    } else {
+      std::cout << "Uncaught error: ";
+      debug_print(errobj);
     }
 
     if (TRY(backtrace.size()) > 0) {