start adding assignment (currently only identifier assignment works)

src/runtime/assignment/assignment.c

@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2025 William Bell
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "assignment.h"
+
+ArErr runtime_assignment(Translated *translated, RuntimeState *state,
+                         struct Stack *stack) {
+  int64_t length = pop_bytecode(translated, state);
+  int64_t offset = pop_bytecode(translated, state);
+  int64_t prehash = pop_bytecode(translated, state);
+  int64_t from_register = pop_byte(translated, state);
+  uint64_t hash =
+      runtime_hash(arena_get(&translated->constants, offset), length, prehash);
+  ArgonObject *key =
+      new_string_object(arena_get(&translated->constants, offset), length);
+  for (Stack *current_stack = stack; current_stack;
+       current_stack = current_stack->prev) {
+    ArgonObject *exists = hashmap_lookup_GC(current_stack->scope, hash);
+    if (exists) {
+      hashmap_insert_GC(current_stack->scope, hash, key,
+                        state->registers[from_register], 0);
+    }
+  }
+  hashmap_insert_GC(stack->scope, hash, key, state->registers[from_register],
+                    0);
+  return no_err;
+}

src/runtime/assignment/assignment.h

@@ -0,0 +1,15 @@
+/*
+ * SPDX-FileCopyrightText: 2025 William Bell
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#ifndef runtime_assignment_H
+#define runtime_assignment_H
+#include "../runtime.h"
+#include "../objects/string/string.h"
+
+ArErr runtime_assignment(Translated *translated, RuntimeState *state,
+                          struct Stack *stack);
+
+#endif // runtime_assignment_H

src/runtime/runtime.c

@@ -12,6 +12,7 @@
 #include "access/access.h"
 #include "call/call.h"
 #include "declaration/declaration.h"
+#include "assignment/assignment.h"
 #include "internals/hashmap/hashmap.h"
 #include "objects/functions/functions.h"
 #include "objects/literals/literals.h"
@@ -679,6 +680,8 @@ ArErr run_instruction(Translated *translated, RuntimeState *state,
     return load_variable(translated, state, *stack);
   case OP_DECLARE:
     return runtime_declaration(translated, state, *stack);
+  case OP_ASSIGN:
+    return runtime_assignment(translated, state, *stack);
   case OP_BOOL:;
     ArErr err = no_err;
     uint8_t to_register = pop_byte(translated, state);