✨ function closures.

lib/compiler.c

@@ -7,8 +7,10 @@
 #include "lib/tysy.h"
 #include "node.h"
 #include "fun.h"
+#include "locals.h"
 
 void compiler_init(compiler_t* compiler,
+                   int* id,
                    sym_t* sym,
                    tysy_t* tysy,
                    err_t* err)
@@ -18,11 +20,13 @@ void compiler_init(compiler_t* compiler,
   assert(tysy);
   assert(err);
 
+  compiler->parent = NULL;
   compiler->sym = sym;
   compiler->tysy = tysy;
   compiler->err = err;
 
   compiler->scope = 0;
+  compiler->id = id;
 }
 
 void compiler_free(compiler_t* compiler)
@@ -281,7 +285,6 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
                                                  compiler->scope,
                                                  SYM_DECL,
                                                  node);
-
       if (!entry)
         {
           char msg[RZ_STR_LIMIT];
@@ -305,6 +308,15 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
                                                 compiler->scope,
                                                 SYM_DECL,
                                                 node);
+
+      if (0 && compiler->parent && !entry)
+        {
+          entry = sym_try_find_by_name(compiler->parent->sym, name,
+                                       compiler->scope,
+                                       SYM_DECL,
+                                       node);
+        }
+
       if (!entry)
         {
           char msg[RZ_STR_LIMIT];
@@ -367,28 +379,39 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
       assert(entry);
 
       entry->state = SYM_DECL;
+      entry->id = *compiler->id;
 
       // Compile function
       {
         compiler_t comp;
-        compiler_init(&comp, (sym_t*) fun->sym,
+        compiler_init(&comp, compiler->id, (sym_t*) fun->sym,
                       compiler->tysy, compiler->err);
+        comp.parent = compiler;
+        comp.sym->parent = compiler->sym;
 
         tysolver_t tysolver;
         tysolver_init(&tysolver, (sym_t*) fun->sym, compiler->tysy);
 
         prepass_t pre;
-        prepass_init(&pre, (sym_t*) fun->sym, compiler->tysy,
+        prepass_init(&pre, compiler->id, (sym_t*) fun->sym, compiler->tysy,
                      &tysolver, compiler->err);
 
+
+        // self
+        int id = sym_declare((sym_t*) fun->sym,
+                             (*compiler->id)++,
+                             fun_name,
+                             tysy_try_find_type(comp.tysy, "fun"),
+                             comp.scope,
+                             SYM_DECL,
+                             node);
+
+
+        fun->base = id;
+
         prepass_run(&pre, (node_t*) node->children.data[2]);
 
-        // self
-        sym_declare((sym_t*) fun->sym, fun_name,
-                    tysy_try_find_type(comp.tysy, "fun"),
-                    comp.scope,
-                    SYM_DECL,
-                    node);
+        fun->arg_base = *compiler->id;
 
         compiler_run(&comp, (node_t*) node->children.data[1], &fun->program);
         compiler_run(&comp, (node_t*) node->children.data[2], &fun->program);
@@ -399,11 +422,11 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
         compiler_free(&comp);
       }
 
-      // value_t* value = tysy_new_fun(compiler->tysy, fun, node->line);
       param_t param = program_push_new_value(program, (struct value*) value);
       program_push_instr(program, OP_PUSH, param);
-
+      program_push_instr(program, OP_MKFUN, RZ_NO_PARAM);
       program_push_instr(program, OP_STORE, entry->id);
+
     } break;
 
     case NODE_PARAMS: {
@@ -411,7 +434,7 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
         {
           node_t* child = (node_t*) node->children.data[i];
           char* name = child->value.data;
-          sym_declare(compiler->sym, name, NULL,
+          sym_declare(compiler->sym, (*compiler->id)++, name, NULL,
                       compiler->scope, SYM_DECL,
                       child);
         }
@@ -436,6 +459,7 @@ int compiler_run(compiler_t* compiler, node_t* node, program_t* program)
                                                 compiler->scope,
                                                 SYM_DECL,
                                                 node);
+
       if (!entry)
         {
           char msg[RZ_STR_LIMIT];

lib/compiler.h

@@ -8,15 +8,18 @@
 #include "tysy.h"
 #include "sym.h"
 
-typedef struct {
+typedef struct compiler {
+  struct compiler* parent;
   sym_t* sym;
   tysy_t* tysy;
   err_t* err;
 
   int scope;
+  int* id;
 } compiler_t;
 
 void compiler_init(compiler_t* compiler,
+                   int* id,
                    sym_t* sym,
                    tysy_t* tysy,
                    err_t* err);

lib/fun.c

@@ -1,12 +1,47 @@
 #include "fun.h"
 #include "sym.h"
+#include "locals.h"
+#include "value.h"
 
 void fun_init(fun_t* fun, struct tysy* tysy, err_t* err)
 {
   assert(fun);
   program_init(&fun->program);
+  fun->err = err;
   fun->sym = malloc(sizeof(sym_t));
   sym_init((sym_t*) fun->sym, (tysy_t*) tysy, err);
+
+  fun->locals = malloc(sizeof(locals_t));
+  locals_init((locals_t*) fun->locals);
+
+  fun->base = 0;
+
+  fun->closure.size = 0;
+  fun->closure.cap = 0;
+  fun->closure.data = NULL;
+}
+
+fun_t* fun_new_clone(fun_t* fun)
+{
+  assert(fun);
+  fun_t* clone = malloc(sizeof(fun_t));
+  fun_init(clone, fun->tysy, fun->err);
+
+  locals_free((locals_t*) clone->locals);
+  free(clone->locals);
+
+  clone->locals = (struct locals*) locals_new_clone((locals_t*) fun->locals);
+  clone->base = fun->base;
+  clone->arg_base = fun->arg_base;
+
+  for (size_t i=0; i<fun->closure.size; i++)
+    {
+      fun_capture(clone,
+                  fun->closure.data[i]->id,
+                  fun->closure.data[i]->value);
+    }
+
+  return clone;
 }
 
 void fun_free(fun_t* fun)
@@ -16,4 +51,59 @@ void fun_free(fun_t* fun)
 
   sym_free((sym_t*) fun->sym);
   free(fun->sym);
+
+  locals_free((locals_t*) fun->locals);
+  free(fun->locals);
+
+  for (size_t i=0; i<fun->closure.size; i++)
+    {
+      value_free((value_t*) fun->closure.data[i]->value);
+      free(fun->closure.data[i]->value);
+      free(fun->closure.data[i]);
+    }
+
+  free(fun->closure.data);
+  fun->closure.data = NULL;
+}
+
+void fun_capture(fun_t* fun, int id, struct value* value)
+{
+  assert(fun);
+  assert(value);
+
+  if (fun->closure.data == NULL)
+    {
+      fun->closure.cap = 2;
+      fun->closure.data = malloc(sizeof(closure_entry_t*) * fun->closure.cap);
+    }
+
+  if (fun->closure.size >= fun->closure.cap)
+    {
+      fun->closure.cap *= 2;
+      fun->closure.data = realloc(fun->closure.data,
+                                  sizeof(closure_entry_t*) * fun->closure.cap);
+    }
+
+
+  fun->closure.data[fun->closure.size] = malloc(sizeof(closure_entry_t));
+  fun->closure.data[fun->closure.size]->id = id;
+  fun->closure.data[fun->closure.size]->value = value_new_clone(value);
+
+  fun->closure.size++;
+}
+
+closure_entry_t* fun_try_find_closure(fun_t* fun, int id)
+{
+  assert(fun);
+
+  for (size_t i=0; i<fun->closure.size; i++)
+    {
+      if (fun->closure.data[i]->id == id)
+        {
+          return fun->closure.data[i];
+        }
+    }
+
+
+  return NULL;
 }

lib/fun.h

@@ -6,15 +6,35 @@
 #include "err.h"
 
 struct sym;
+struct locals;
+struct value;
+
+typedef struct {
+  int id;
+  struct value* value;
+} closure_entry_t;
 
 typedef struct {
   program_t program;
+  err_t* err;
   struct sym* sym;
   struct tysy* tysy;
+  struct locals* locals;
+  int base;
+  int arg_base;
+  struct {
+    size_t size;
+    size_t cap;
+    closure_entry_t** data;
+  } closure;
+
 } fun_t;
 
 void fun_init(fun_t* fun, struct tysy* tysy, err_t* err);
+fun_t* fun_new_clone(fun_t* fun);
 void fun_free(fun_t* fun);
 
+void fun_capture(fun_t* fun, int id, struct value* value);
+closure_entry_t* fun_try_find_closure(fun_t* fun, int id);
 
 #endif

lib/heap.c

@@ -0,0 +1,55 @@
+#include "heap.h"
+
+void heap_init(heap_t* heap)
+{
+  assert(heap);
+
+  heap->size = 0;
+  heap->cap = 0;
+  heap->data = NULL;
+}
+
+void heap_free(heap_t* heap)
+{
+  for (size_t i=0; i<heap->size; i++)
+    {
+      //value_free(heap->data[i]);
+      //free(heap->data[i]);
+    }
+
+  free(heap->data);
+
+  heap->size = 0;
+  heap->cap = 0;
+  heap->data = NULL;
+}
+
+size_t heap_alloc(heap_t* heap, value_t* value)
+{
+  assert(heap);
+
+  if (heap->data == NULL)
+    {
+      heap->cap = 2;
+      heap->data = malloc(sizeof(value_t*) * heap->cap);
+    }
+
+  if (heap->size >= heap->cap)
+    {
+      heap->cap *= 2;
+      heap->data = realloc(heap->data, sizeof(value_t*) * heap->cap);
+    }
+
+  heap->data[heap->size] = value;
+  heap->size++;
+
+  return heap->size - 1;
+}
+
+value_t* heap_deref(heap_t* heap, size_t addr)
+{
+  assert(heap);
+  assert(addr < heap->size);
+
+  return heap->data[addr];
+}

lib/heap.h

@@ -0,0 +1,19 @@
+#ifndef RZ_HEAP_H
+#define RZ_HEAP_H
+
+#include "commons.h"
+#include "value.h"
+
+typedef struct {
+  size_t cap;
+  size_t size;
+  value_t** data;
+} heap_t;
+
+void heap_init(heap_t* heap);
+void heap_free(heap_t* heap);
+
+size_t heap_alloc(heap_t* heap, value_t* value);
+value_t* heap_deref(heap_t* heap, size_t addr);
+
+#endif

lib/loader.c

@@ -104,11 +104,12 @@ int loader_ldfile(loader_t* loader, char const* path, int debug)
 
   tysolver_t tysolver;
   tysolver_init(&tysolver, &sym, &tysy);
+  int id = 0;
 
   // prepass
   {
     prepass_t prepass;
-    prepass_init(&prepass, &sym, &tysy, &tysolver, &err);
+    prepass_init(&prepass, &id, &sym, &tysy, &tysolver, &err);
     prepass_run(&prepass, node);
     prepass_free(&prepass);
   }
@@ -116,7 +117,7 @@ int loader_ldfile(loader_t* loader, char const* path, int debug)
   // compile
   {
     compiler_t compiler;
-    compiler_init(&compiler, &sym, &tysy, &err);
+    compiler_init(&compiler, &id, &sym, &tysy, &err);
     int status = compiler_run(&compiler, node, &mod.program);
 
     if (status != 0)

lib/locals.c

@@ -0,0 +1,90 @@
+#include "locals.h"
+
+void locals_init(locals_t* locals)
+{
+  assert(locals);
+
+  locals->cap = 0;
+  locals->size = 0;
+  locals->data = NULL;
+}
+
+locals_t* locals_new_clone(locals_t* locals)
+{
+  assert(locals);
+
+  locals_t* clone = malloc(sizeof(locals_t));
+  locals_init(clone);
+
+  for (size_t i=0; i<locals->size; i++)
+    {
+      locals_store(clone,
+                   locals->data[i]->id,
+                   locals->data[i]->addr);
+    }
+
+  return clone;
+}
+
+void locals_free(locals_t* locals)
+{
+  assert(locals);
+
+    for (size_t i=0; i<locals->size; i++)
+    {
+      free(locals->data[i]);
+    }
+
+  free(locals->data);
+  locals->data = NULL;
+  locals->size = 0;
+  locals->cap = 0;
+}
+
+local_t* locals_try_load(locals_t* locals, int id)
+{
+  assert(locals);
+
+  for (size_t i=0; i<locals->size; i++)
+    {
+      if (locals->data[i]->id == id)
+        {
+          return locals->data[i];
+        }
+    }
+
+  return NULL;
+}
+
+void locals_store(locals_t* locals, int id, int addr)
+{
+  assert(locals);
+
+  local_t* loc = locals_try_load(locals, id);
+
+  if (!loc)
+    {
+      if (locals->data == NULL)
+        {
+          locals->cap = 2;
+          locals->data = malloc(sizeof(local_t*) * locals->cap);
+        }
+
+      if (locals->size >= locals->cap)
+        {
+          locals->cap *= 2;
+          locals->data = realloc(locals->data,
+                                 sizeof(local_t*) * locals->cap);
+        }
+
+      locals->data[locals->size] = malloc(sizeof(local_t));
+      locals->data[locals->size]->id = id;
+      locals->data[locals->size]->addr = addr;
+      locals->size++;
+    }
+  else
+    {
+      loc->id = id;
+      loc->addr = addr;
+    }
+}

lib/locals.h

@@ -0,0 +1,25 @@
+#ifndef RZ_LOCALS_H
+#define RZ_LOCALS_H
+
+#include "commons.h"
+#include "value.h"
+
+typedef struct {
+  int id;
+  int addr;
+} local_t;
+
+typedef struct {
+    size_t size;
+    size_t cap;
+    local_t** data;
+} locals_t;
+
+void locals_init(locals_t* locals);
+locals_t* locals_new_clone(locals_t* locals);
+void locals_free(locals_t* locals);
+
+local_t* locals_try_load(locals_t* locals, int id);
+void locals_store(locals_t* locals, int id, int addr);
+
+#endif

lib/opcodes.h

@@ -14,7 +14,8 @@
     G(OP_BRF), G(OP_BRT), G(OP_BR),             \
     G(OP_STRCAT), G(OP_STRDUP),                 \
     G(OP_LOAD), G(OP_STORE),                    \
-    G(OP_CALL), G(OP_RET)
+    G(OP_CALL), G(OP_RET), G(OP_MKFUN),         \
+    G(OP_ALLOC), G(OP_DEREF)
 
 
 RZ_ENUM_H(Opcode, OPCODES);

lib/prepass.c

@@ -4,6 +4,7 @@
 #include "node.h"
 
 void prepass_init(prepass_t* prepass,
+                  int* id,
                   sym_t* sym,
                   tysy_t* tysy,
                   tysolver_t* tysolver,
@@ -21,6 +22,7 @@ void prepass_init(prepass_t* prepass,
   prepass->err = err;
 
   prepass->scope = 0;
+  prepass->id = id;
 }
 
 void prepass_free(prepass_t* prepass)
@@ -55,7 +57,7 @@ void prepass_run(prepass_t* prepass, node_t* node)
       type_t* type = tysolver_try_solve_node(prepass->tysolver,
                                              (node_t*) node->children.data[1]);
 
-      sym_declare(prepass->sym, name, type,
+      sym_declare(prepass->sym, (*prepass->id)++, name, type,
                   prepass->scope, SYM_PRE,
                   node);
 
@@ -64,7 +66,9 @@ void prepass_run(prepass_t* prepass, node_t* node)
     case NODE_FUNDECL: {
       char* name = ((node_t*) node->children.data[0])->value.data;
 
-      sym_declare(prepass->sym, name,
+      sym_declare(prepass->sym,
+                  (*prepass->id)++,
+                  name,
                   tysy_try_find_type(prepass->tysy, "fun"),
                   prepass->scope,
                   SYM_PRE,

lib/prepass.h

@@ -13,12 +13,13 @@ typedef struct {
   tysy_t* tysy;
   tysolver_t* tysolver;
   err_t* err;
-
+  int* id;
   int scope;
 
 } prepass_t;
 
 void prepass_init(prepass_t* prepass,
+                  int* id,
                   sym_t* sym,
                   tysy_t* tysy,
                   tysolver_t* tysolver,

lib/sym.c

@@ -4,10 +4,9 @@
 void sym_init(sym_t* sym, tysy_t* tysy, err_t* err)
 {
   assert(sym);
-
+  sym->parent = NULL;
   sym->tysy = tysy;
   sym->err = err;
-
   sym->entries.id_counter = 0;
   sym->entries.size = 0;
   sym->entries.cap = 0;
@@ -30,7 +29,7 @@ void sym_free(sym_t* sym)
   sym->entries.cap = 0;
 }
 
-int sym_declare(sym_t* sym, char* name, type_t* type,
+int sym_declare(sym_t* sym, int id, char* name, type_t* type,
                 int scope, int state_flag, node_t* node)
 {
   assert(sym);
@@ -72,9 +71,6 @@ int sym_declare(sym_t* sym, char* name, type_t* type,
 
   sym->entries.data[sym->entries.size] = malloc(sizeof(sym_entry_t));
 
-  int id = sym->entries.id_counter;
-  sym->entries.id_counter++;
-
   sym->entries.data[sym->entries.size]->name = strdup(name);
   sym->entries.data[sym->entries.size]->id = id;
   sym->entries.data[sym->entries.size]->type = type;
@@ -117,9 +113,20 @@ sym_entry_t* sym_try_find_by_name(sym_t* sym, char* name,
         }
     }
 
+  sym_entry_t* result = NULL;
+
   if (scope > 0)
     {
-      return sym_try_find_by_name(sym, name, scope - 1, state_flag, node);
+      result = sym_try_find_by_name(sym, name, scope - 1, state_flag, node);
+
+      if (result) { return result; }
+    }
+
+  if (sym->parent)
+    {
+      result = sym_try_find_by_name(sym->parent, name, scope, state_flag, node);
+
+      if (result) { return result; }
     }
 
   return NULL;

lib/sym.h

@@ -20,9 +20,10 @@ typedef struct {
   node_t* node;
 } sym_entry_t;
 
-typedef struct {
+typedef struct sym {
   tysy_t* tysy;
   err_t* err;
+  struct sym* parent;
 
   struct {
     int id_counter;
@@ -35,7 +36,7 @@ typedef struct {
 void sym_init(sym_t* sym, tysy_t* tysy, err_t* err);
 void sym_free(sym_t* sym);
 
-int sym_declare(sym_t* sym, char* name, type_t* type,
+int sym_declare(sym_t* sym, int id, char* name, type_t* type,
                 int scope, int state_flag,
                 node_t* node);
 

lib/type.h

@@ -5,7 +5,7 @@
 
 #define TYPE_KIND(G)                            \
   G(TYPE_NUM), G(TYPE_BOOL), G(TYPE_STR),       \
-    G(TYPE_FUN)
+    G(TYPE_FUN), G(TYPE_REF)
 
 RZ_ENUM_H(TypeKind, TYPE_KIND);
 

lib/tysy.c

@@ -32,6 +32,13 @@ void tysy_init(tysy_t* tysy)
     type_init(ty, TYPE_FUN);
     tysy_register_new_type(tysy, "fun", ty);
   }
+
+  // ref
+  {
+    type_t* ty = malloc(sizeof(type_t));
+    type_init(ty, TYPE_REF);
+    tysy_register_new_type(tysy, "ref", ty);
+  }
 }
 
 void tysy_free(tysy_t* tysy)
@@ -119,3 +126,14 @@ value_t* tysy_new_fun(tysy_t* tysy, fun_t* fun, int line)
 
   return val;
 }
+
+value_t* tysy_new_ref(tysy_t* tysy, size_t ref, int line)
+{
+  assert(tysy);
+
+  value_t* val = malloc(sizeof(value_t));
+  value_init(val, tysy_try_find_type(tysy, "ref"), line);
+  val->value.ref = ref;
+
+  return val;
+}

lib/tysy.h

@@ -20,5 +20,6 @@ value_t* tysy_new_num(tysy_t* tysy, double value, int line);
 value_t* tysy_new_bool(tysy_t* tysy, int value, int line);
 value_t* tysy_new_str(tysy_t* tysy, char* value, int line);
 value_t* tysy_new_fun(tysy_t* tysy, fun_t* fun, int line);
+value_t* tysy_new_ref(tysy_t* tysy, size_t ref, int line);
 
 #endif

lib/value.c

@@ -12,6 +12,27 @@ void value_init(value_t* value, type_t* type, int line)
   value->line = line;
 }
 
+value_t* value_new_clone(value_t* value)
+{
+  assert(value);
+  value_t* clone = malloc(sizeof(value_t));
+  value_init(clone, value->type, value->line);
+
+  clone->value = value->value;
+
+  if (value->type->kind == TYPE_STR)
+    {
+      clone->value.str = strdup(value->value.str);
+    }
+
+  if (value->type->kind == TYPE_FUN)
+    {
+      clone->value.fun = fun_new_clone(value->value.fun);
+    }
+
+  return clone;
+}
+
 void value_free(value_t* value)
 {
   assert(value);
@@ -56,6 +77,10 @@ int value_eq(value_t* value, value_t* rhs)
       return value->value.fun == rhs->value.fun;
     } break;
 
+    case TYPE_REF: {
+      return value->value.ref == rhs->value.ref;
+    } break;
+
     default: {
       fprintf(stderr, "Cannot compare value of type '%s'.\n",
               TypeKindStr[value->type->kind]);
@@ -89,6 +114,10 @@ size_t value_str(value_t* value, char* buffer, size_t size)
       return snprintf(buffer, size, "[fun]");
       break;
 
+    case TYPE_REF:
+      return snprintf(buffer, size, "[ref %d]", (int) value->value.ref);
+      break;
+
     default: {
       fprintf(stderr, "Cannot stringify unknown value of type '%s'.\n",
               TypeKindStr[value->type->kind]);

lib/value.h

@@ -6,12 +6,13 @@
 
 struct program;
 
-typedef struct {
+typedef struct value {
   type_t* type;
 
   union {
     double num;
     int bool;
+    size_t ref;
     char* str;
     fun_t* fun;
   } value;
@@ -20,6 +21,7 @@ typedef struct {
 } value_t;
 
 void value_init(value_t* value, type_t* type, int line);
+value_t* value_new_clone(value_t* value);
 void value_free(value_t* value);
 
 int value_eq(value_t* value, value_t* rhs);

lib/vm.c

@@ -1,5 +1,8 @@
 #include "vm.h"
 #include "lib/commons.h"
+#include "lib/fun.h"
+#include "lib/heap.h"
+#include "lib/locals.h"
 #include "lib/mod.h"
 #include "lib/type.h"
 #include "lib/tysy.h"
@@ -13,10 +16,13 @@ void vm_init(vm_t* vm, sym_t* sym, tysy_t* tysy, err_t* err)
   assert(tysy);
 
   vm->top_frame = NULL;
+  locals_init(&vm->locals);
   vm_frame_push(vm, NULL);
 
   vm->tysy = tysy;
   vm->err = err;
+
+  heap_init(&vm->heap);
 }
 
 void vm_free(vm_t* vm)
@@ -34,21 +40,26 @@ void vm_free(vm_t* vm)
     }
 
   vm->top_frame = NULL;
+
+  heap_free(&vm->heap);
+
+  locals_free(&vm->locals);
 }
 
 void vm_frame_init(frame_t* frame)
 {
   assert(frame);
 
+  frame->fun = NULL;
+
   frame->pc = 0;
   frame->bp = 0;
   frame->sp = 0;
 
   frame->prev = NULL;
   frame->program = NULL;
-  frame->locals.cap = 0;
-  frame->locals.size = 0;
-  frame->locals.data = NULL;
+
+  frame->locals = NULL;
 
   frame->alloc.cap = 0;
   frame->alloc.size = 0;
@@ -57,18 +68,6 @@ void vm_frame_init(frame_t* frame)
 
 void vm_frame_free(frame_t* frame)
 {
-  for (size_t i=0; i<frame->locals.size; i++)
-    {
-      free(frame->locals.data[i]);
-    }
-
-  free(frame->locals.data);
-  frame->locals.data = NULL;
-  frame->locals.size = 0;
-  frame->locals.cap = 0;
-
-  //vm_clear_alloc(frame);
-
   if (frame->prev != NULL)
     {
       vm_frame_free((frame_t*) frame->prev);
@@ -76,7 +75,7 @@ void vm_frame_free(frame_t* frame)
     }
 }
 
-void vm_frame_push(vm_t* vm, program_t* program)
+void vm_frame_push(vm_t* vm, fun_t* fun)
 {
   assert(vm);
 
@@ -84,7 +83,17 @@ void vm_frame_push(vm_t* vm, program_t* program)
   vm_frame_init(frame);
 
   frame->prev = (struct frame*) vm->top_frame;
-  frame->program = program;
+
+  if (fun != NULL)
+    {
+      frame->program = &fun->program;
+      frame->locals = (locals_t*) fun->locals;
+    }
+  else
+    {
+      frame->locals = &vm->locals;
+    }
+
   vm->top_frame = frame;
 }
 
@@ -92,6 +101,13 @@ int vm_frame_pop(vm_t* vm)
 {
   assert(vm);
 
+  if (vm->top_frame->fun)
+    {
+      fun_free(vm->top_frame->fun);
+      free(vm->top_frame->fun);
+      vm->top_frame->fun = NULL;
+    }
+
   if (vm->top_frame)
     {
       vm_clear_alloc(vm->top_frame);
@@ -113,57 +129,6 @@ int vm_frame_pop(vm_t* vm)
   return 0;
 }
 
-local_t* vm_try_local_load(vm_t* vm, int id)
-{
-  assert(vm);
-
-  for (size_t i=0; i<vm->top_frame->locals.size; i++)
-    {
-      if (vm->top_frame->locals.data[i]->id == id)
-        {
-          return vm->top_frame->locals.data[i];
-        }
-    }
-
-  return NULL;
-}
-
-void vm_local_store(vm_t* vm, int id, param_t addr)
-{
-  assert(vm);
-  local_t* loc = vm_try_local_load(vm, id);
-
-  if (!loc)
-    {
-      if (vm->top_frame->locals.data == NULL)
-        {
-          vm->top_frame->locals.cap = 2;
-          vm->top_frame->locals.data = malloc(sizeof(local_t*)
-                                              * vm->top_frame->locals.cap);
-        }
-
-      if (vm->top_frame->locals.size >= vm->top_frame->locals.cap)
-        {
-          vm->top_frame->locals.cap *= 2;
-          vm->top_frame->locals.data = realloc(vm->top_frame->locals.data,
-                                               sizeof(local_t*)
-                                               * vm->top_frame->locals.cap);
-        }
-
-      vm->top_frame->locals.data[vm->top_frame->locals.size]
-        = malloc(sizeof(local_t));
-
-      vm->top_frame->locals.data[vm->top_frame->locals.size]->id = id;
-      vm->top_frame->locals.data[vm->top_frame->locals.size]->addr = addr;
-      vm->top_frame->locals.size++;
-    }
-  else
-    {
-      loc->id = id;
-      loc->addr = addr;
-    }
-}
-
 void vm_push_new(vm_t* vm, value_t* value)
 {
   assert(value);
@@ -465,7 +430,25 @@ int vm_exec_instr(vm_t* vm, Opcode op, param_t param)
     } break;
 
     case OP_LOAD: {
-      local_t* local = vm_try_local_load(vm, param);
+      local_t* local = locals_try_load(vm->top_frame->locals, param);
+
+      if (!local && vm->top_frame->fun)
+        {
+          fun_t* fun = vm->top_frame->fun;
+          closure_entry_t* e = fun_try_find_closure(fun, param);
+
+          if (e)
+            {
+              vm_push(vm, e->value);
+              vm->top_frame->pc++;
+              break;
+            }
+        }
+
+      if (!local)
+        {
+          local = locals_try_load(&vm->locals, param);
+        }
 
       if (!local)
         {
@@ -492,6 +475,7 @@ int vm_exec_instr(vm_t* vm, Opcode op, param_t param)
         }
       else
         {
+          assert(local->addr < vm->top_frame->sp);
           vm_push(vm, vm->top_frame->stack[local->addr]);
         }
 
@@ -500,39 +484,120 @@ int vm_exec_instr(vm_t* vm, Opcode op, param_t param)
 
     case OP_STORE: {
       assert(vm->top_frame->sp > 0);
-      vm_local_store(vm, param, vm->top_frame->sp - 1);
+
+      if (vm->top_frame->fun)
+        {
+
+          fun_t* fun = vm->top_frame->fun;
+
+          closure_entry_t* closure = fun_try_find_closure(fun, param);
+
+          if (closure)
+            {
+              value_t* value = vm->top_frame->stack[vm->top_frame->sp - 1];
+              value_free(closure->value);
+              free(closure->value);
+              closure->value = value_new_clone(value);
+              vm->top_frame->pc++;
+              break;
+            }
+        }
+
+      locals_store(vm->top_frame->locals, param, vm->top_frame->sp - 1);
+      vm->top_frame->pc++;
+    } break;
+
+    case OP_MKFUN: {
+      value_t* value = vm_pop(vm);
+      size_t addr = heap_alloc(&vm->heap, value);
+
+      value_t* ref = tysy_new_ref(vm->tysy, addr, value->line);
+      vm_push_new(vm, ref);
+
+      frame_t* prev = (frame_t*) vm->top_frame->prev;
+      locals_t* loc = &vm->locals;
+
+      assert(value->type->kind == TYPE_FUN);
+      fun_t* fun = value->value.fun;
+
+      if (vm->top_frame->fun)
+        {
+          loc = (locals_t*) vm->top_frame->fun->locals;
+        }
+      else if (prev && prev->fun)
+        {
+          loc = (locals_t*) prev->fun->locals;
+        }
+      else if (prev)
+        {
+          loc = prev->locals;
+        }
+
+      if (loc)
+        {
+          for (size_t i=0; i<loc->size; i++)
+            {
+              int id = vm->top_frame->locals->data[i]->id;
+              value_t* loc_val = vm->top_frame->stack[addr];
+
+              fun_capture(fun, id, loc_val);
+            }
+        }
+
+      vm->top_frame->pc++;
+    } break;
+
+    case OP_DEREF: {
+      value_t* value = vm_pop(vm);
+
+      assert(value->type->kind == TYPE_REF);
+
+      size_t addr = value->value.ref;
+
+      vm_push(vm, heap_deref(&vm->heap, addr));
       vm->top_frame->pc++;
     } break;
 
     case OP_CALL: {
-      size_t const ARG_SZ = param + 1;
+      size_t const ARG_SZ = param;
       value_t* args[ARG_SZ];
 
+      value_t* fun_ref = vm_pop(vm);
+
       for (size_t i=0; i<ARG_SZ; i++)
         {
           value_t* val = vm_pop(vm);
-          args[ARG_SZ - 1 - i] = val;
+          args[i] = val;
         }
 
-      value_t* fun_val = args[ARG_SZ - 1];
+      value_t* fun_val = heap_deref(&vm->heap, fun_ref->value.ref);
+
       assert(fun_val->type->kind == TYPE_FUN);
-      fun_t* fun = fun_val->value.fun;
+
+      fun_t* fun = fun_new_clone(fun_val->value.fun);
 
       vm->top_frame->pc++;
-      vm_frame_push(vm, &fun->program);
+      vm_frame_push(vm, fun);
+      vm->top_frame->fun = fun;
+
+      vm_push(vm, fun_ref);
+      locals_store(vm->top_frame->locals, fun->base, vm->top_frame->sp - 1);
 
       for (size_t i=0; i<ARG_SZ; i++)
         {
           value_t* arg = args[i];
+          size_t addr = fun->arg_base + (ARG_SZ - 1 - i);
 
           vm_push(vm, arg);
-          vm_local_store(vm, ARG_SZ - 1 - i, vm->top_frame->sp - 1);
+
+          locals_store(vm->top_frame->locals,
+                       addr,
+                       vm->top_frame->sp - 1);
         }
 
     } break;
 
     case OP_RET: {
-
       frame_t* frame = (frame_t*) vm->top_frame;
       frame_t* prev = (frame_t*) vm->top_frame->prev;
 

lib/vm.h

@@ -8,11 +8,8 @@
 #include "tysy.h"
 #include "sym.h"
 #include "program.h"
-
-typedef struct {
-  int id;
-  param_t addr;
-} local_t;
+#include "heap.h"
+#include "locals.h"
 
 typedef struct stack_frame{
   struct frame* prev;
@@ -22,12 +19,8 @@ typedef struct stack_frame{
   size_t pc;
   size_t bp;
   size_t sp;
-
-  struct {
-    size_t size;
-    size_t cap;
-    local_t** data;
-  } locals;
+  fun_t* fun;
+  locals_t* locals;
 
   struct {
     size_t size;
@@ -42,6 +35,8 @@ typedef struct {
   tysy_t* tysy;
   err_t* err;
   frame_t* top_frame;
+  heap_t heap;
+  locals_t locals;
 } vm_t;
 
 void vm_init(vm_t* vm, sym_t* sym, tysy_t* tysy, err_t* err);
@@ -50,12 +45,9 @@ void vm_free(vm_t* vm);
 void vm_frame_init(frame_t* frame);
 void vm_frame_free(frame_t* frame);
 
-void vm_frame_push(vm_t* vm, program_t* program);
+void vm_frame_push(vm_t* vm, fun_t* fun);
 int vm_frame_pop(vm_t* vm);
 
-local_t* vm_try_local_load(vm_t* vm, int id);
-void vm_local_store(vm_t* vm, int id, param_t addr);
-
 void vm_push_new(vm_t* vm, value_t* value);
 void vm_push(vm_t* vm, value_t* value);
 value_t* vm_pop(vm_t* vm);

meson.build

@@ -48,6 +48,8 @@ roza_lib = static_library(
 
     # exec
     'lib/vm.c',
+    'lib/heap.c',
+    'lib/locals.c',
   ],
 
   dependencies: [

tests/acceptances/fun.roza

@@ -1,6 +1,5 @@
 # FUNCTIONS
 # =========
-
 fun double(n)
   n * 2
 end
@@ -38,7 +37,6 @@ assert max(7, 9) == 9
 
 # RECURSIVITY
 # ===========
-
 fun fac(n)
   if n == 0 then
     return 1
@@ -57,4 +55,61 @@ fun fib(n)
   return fib(n - 2) + fib(n - 1)
 end
 
-assert fib(6) == 13
+assert fib(6) == 13
+
+# HIGH ORDER FUNCTIONS
+# ====================
+fun fi(n)
+  return n + 1
+end
+
+fun fd(n)
+  return n * 2
+end
+
+fun twice(f, x)
+  return f(f(x))
+end
+
+assert twice(fi, 27) == 29
+assert twice(fd, 12) == 48
+
+# CLOSURES
+# ========
+fun make()
+  let counter = 0
+
+  fun inner()
+    counter = counter + 1
+    return counter - 1
+  end
+
+  return inner
+end
+
+let c = make()
+
+assert c() == 0
+assert c() == 1
+assert c() == 2
+
+fun make_val(init)
+  let counter = init
+
+  fun inner()
+    counter = counter + 1
+    return counter - 1
+  end
+
+  return inner
+end
+
+let d = make_val(7)
+let e = make_val(3)
+
+assert d() == 7
+assert e() == 3
+assert d() == 8
+assert e() == 4
+assert d() == 9
+assert e() == 5