next: *

examples/fizzbuzz.grr

@@ -1,4 +1,13 @@
-#load("std.grr")
+def print { file/stdout file/write }
+def when { [] if }
+def keep { over [call] dip }
+def bi { [keep] dip call }
+
+def times {
+  if: over 0 =
+    [drop drop]
+    [swap over >r >r call r> 1 - r> times];
+}
 
 def fizzbuzz? { [3 % 0 =] [5 % 0 =] bi or }
 def fizz { when: 3 % 0 = ["Fizz" print]; }
@@ -6,7 +15,7 @@ def buzz { when: 5 % 0 = ["Buzz" print]; }
 
 def fizzbuzz1 {
   if: fizzbuzz?
-    [ [fizz] keep buzz nl ]
+    [ [fizz] keep buzz "\n" print ]
     [ . ];
 }
 

meson.build

@@ -51,10 +51,12 @@ growlnext_sources = [
     'next/core/compiler.c',
     'next/core/dictionary.c',
     'next/core/disasm.c',
+    'next/core/file.c',
     'next/core/gc.c',
     'next/core/hash.c',
     'next/core/lexer.c',
     'next/core/list.c',
+    'next/core/native.c',
     'next/core/print.c',
     'next/core/sleb128.c',
     'next/core/string.c',
@@ -65,9 +67,13 @@ growlnext_sources = [
     'next/main.c',
 ]
 
+cc = meson.get_compiler('c')
+m_dep = cc.find_library('m', required: false)
+
 growlnext = executable(
     'growlnext',
     growlnext_sources,
+    dependencies: [m_dep],
     include_directories: ['next/include'],
     install: true,
 )

next/core/alien.c

@@ -10,6 +10,16 @@ Growl growl_make_alien(GrowlVM *vm, GrowlAlienType *type, void *data) {
   return GROWL_BOX(hdr);
 }
 
+Growl growl_make_alien_tenured(GrowlVM *vm, GrowlAlienType *type, void *data) {
+  size_t size = sizeof(GrowlObjectHeader) + sizeof(GrowlAlien);
+  GrowlObjectHeader *hdr = growl_gc_alloc_tenured(vm, size);
+  hdr->type = GROWL_TYPE_ALIEN;
+  GrowlAlien *alien = (GrowlAlien *)(hdr + 1);
+  alien->type = type;
+  alien->data = data;
+  return GROWL_BOX(hdr);
+}
+
 GrowlAlien *growl_unwrap_alien(Growl obj, GrowlAlienType *type) {
   if (obj == GROWL_NIL || GROWL_IMM(obj))
     return NULL;

next/core/compiler.c

@@ -6,6 +6,9 @@
 
 #include "opcodes.h"
 #include "sleb128.h"
+#include "dynarray.h"
+
+#define COMPILER_DEBUG 0
 
 typedef struct {
   Growl *data;
@@ -46,12 +49,15 @@ Primitive primitives[] = {
   {"call",    {GOP_CALL, 0}},
   {"compose", {GOP_COMPOSE, 0}},
   {"curry",   {GOP_CURRY, 0}},
+  {"dip",     {GOP_DIP, 0}},
   {".",       {GOP_PPRINT, 0}},
   {"+",       {GOP_ADD, 0}},
   {"*",       {GOP_MUL, 0}},
   {"-",       {GOP_SUB, 0}},
   {"/",       {GOP_DIV, 0}},
   {"%",       {GOP_MOD, 0}},
+  {"and",     {GOP_AND, 0}},
+  {"or",      {GOP_OR, 0}},
   {"=",       {GOP_EQ, 0}},
   {"!=",      {GOP_NEQ, 0}},
   {"<",       {GOP_LT, 0}},
@@ -66,40 +72,6 @@ Primitive primitives[] = {
 };
 // clang-format on
 
-// See https://nullprogram.com/blog/2023/10/05/
-#define push(s, a)                                                             \
-  ({                                                                           \
-    typeof(s) s_ = (s);                                                        \
-    typeof(a) a_ = (a);                                                        \
-    if (s_->count >= s_->capacity) {                                           \
-      grow(s_, sizeof(*s_->data), _Alignof(*s_->data), a_);                    \
-    }                                                                          \
-    s_->data + s_->count++;                                                    \
-  })
-
-static void grow(void *slice, ptrdiff_t size, ptrdiff_t align, GrowlArena *a) {
-  struct {
-    uint8_t *data;
-    ptrdiff_t len;
-    ptrdiff_t cap;
-  } replica;
-  memcpy(&replica, slice, sizeof(replica));
-
-  if (!replica.data) {
-    replica.cap = 1;
-    replica.data = growl_arena_alloc(a, 2 * size, align, replica.cap);
-  } else if (a->free == replica.data + size * replica.cap) {
-    growl_arena_alloc(a, size, 1, replica.cap);
-  } else {
-    void *data = growl_arena_alloc(a, 2 * size, align, replica.cap);
-    memcpy(data, replica.data, size * replica.len);
-    replica.data = data;
-  }
-
-  replica.cap *= 2;
-  memcpy(slice, &replica, sizeof(replica));
-}
-
 static void emit_byte(GrowlVM *vm, Chunk *chunk, uint8_t byte) {
   *push(chunk, &vm->scratch) = byte;
 }
@@ -160,10 +132,8 @@ static void optimize_tail_calls(Chunk *chunk) {
     }
     if (i < chunk->count && chunk->data[i] == GOP_RETURN) {
       if (opcode == GOP_CALL) {
-        chunk->data[i] = GOP_NOP;
         chunk->data[start] = GOP_TAIL_CALL;
       } else if (opcode == GOP_WORD) {
-        chunk->data[i] = GOP_NOP;
         chunk->data[start] = GOP_TAIL_WORD;
       }
     }
@@ -200,7 +170,7 @@ static int compile_quotation(GrowlVM *vm, GrowlLexer *lexer, Chunk *chunk) {
 }
 
 static int compile_string(GrowlVM *vm, GrowlLexer *lexer, Chunk *chunk) {
-  Growl str = growl_wrap_string(vm, lexer->buffer);
+  Growl str = growl_wrap_string_tenured(vm, lexer->buffer);
   size_t const_idx = add_constant(vm, chunk, str);
   emit_byte(vm, chunk, GOP_PUSH_CONSTANT);
   emit_sleb128(vm, chunk, (intptr_t)const_idx);
@@ -222,6 +192,15 @@ static int compile_def(GrowlVM *vm, GrowlLexer *lexer) {
     return 1;
   }
 
+  // Add a forward declaration to the dictionary so the word can reference itself
+  GrowlDictionary *entry =
+      growl_dictionary_upsert(&vm->dictionary, name, &vm->arena);
+  GrowlDefinition *def = push(&vm->defs, &vm->arena);
+  def->name = growl_arena_strdup(&vm->arena, name);
+  def->callable = GROWL_NIL; // Placeholder, will be filled in after compilation
+  entry->callable = GROWL_NIL;
+  entry->index = vm->defs.count - 1;
+
   growl_lexer_next(lexer);
   Chunk fn_chunk = {0};
   while (lexer->kind != GTOK_RBRACE && lexer->kind != GTOK_EOF &&
@@ -241,14 +220,16 @@ static int compile_def(GrowlVM *vm, GrowlLexer *lexer) {
   Growl fn =
       growl_make_quotation(vm, fn_chunk.data, fn_chunk.count,
                            fn_chunk.constants.data, fn_chunk.constants.count);
-  GrowlQuotation *quot = (GrowlQuotation *)(GROWL_UNBOX(fn) + 1);
+
-  GrowlDictionary *entry =
+#if COMPILER_DEBUG
-      growl_dictionary_upsert(&vm->dictionary, name, &vm->arena);
+  GrowlQuotation *quot = growl_unwrap_quotation(fn);
-  GrowlDefinition *def = push(&vm->defs, &vm->arena);
+  fprintf(stderr, "=== %s ===\n", def->name);
-  def->name = growl_arena_strdup(&vm->arena, name);
+  growl_disassemble(vm, quot);
-  def->quotation = quot;
+#endif
-  entry->quotation = quot;
+
-  entry->index = vm->defs.count - 1;
+  // Now update the definition with the compiled quotation
+  def->callable = fn;
+  entry->callable = fn;
 
   growl_lexer_next(lexer);
   return 0;

next/core/disasm.c

@@ -7,15 +7,15 @@ static void disassemble(GrowlVM *vm, GrowlQuotation *quot, int indent);
 static size_t disassemble_instr(GrowlVM *vm, GrowlQuotation *quot,
                                 size_t offset, int indent) {
   for (int i = 0; i < indent; i++) {
-    printf("  ");
+    fprintf(stderr, "  ");
   }
-  printf("%04zu ", offset);
+  fprintf(stderr, "%04zu ", offset);
 
   uint8_t opcode = quot->data[offset++];
 
   // clang-format off
 #define OPCODE(name) case GOP_## name:
-#define OPCODE1(name) case GOP_## name: printf(#name "\n"); return offset;
+#define OPCODE1(name) case GOP_## name: fprintf(stderr, #name "\n"); return offset;
   // clang-format on
 
   switch (opcode) {
@@ -24,26 +24,26 @@ static size_t disassemble_instr(GrowlVM *vm, GrowlQuotation *quot,
     OPCODE(PUSH_CONSTANT) {
       intptr_t idx;
       size_t bytes_read = growl_sleb128_peek(&quot->data[offset], &idx);
-      printf("PUSH_CONSTANT %ld", idx);
+      fprintf(stderr, "PUSH_CONSTANT %ld", idx);
       if (quot->constants != GROWL_NIL &&
           growl_type(quot->constants) == GROWL_TYPE_TUPLE) {
         GrowlTuple *constants = growl_unwrap_tuple(quot->constants);
         if (idx >= 0 && (size_t)idx < constants->count) {
           Growl constant = constants->data[idx];
-          printf(" (");
+          fprintf(stderr, " (");
-          growl_print(constant);
+          growl_print_to(stderr, constant);
-          printf(")");
+          fprintf(stderr, ")");
 
           if (!GROWL_IMM(constant) && constant != GROWL_NIL &&
               growl_type(constant) == GROWL_TYPE_QUOTATION) {
-            putchar('\n');
+            putc('\n', stderr);
             GrowlQuotation *inner = growl_unwrap_quotation(constant);
             disassemble(vm, inner, indent + 1);
             return offset + bytes_read;
           }
         }
       }
-      putchar('\n');
+      putc('\n', stderr);
       return offset + bytes_read;
     }
     OPCODE1(DROP);
@@ -61,22 +61,24 @@ static size_t disassemble_instr(GrowlVM *vm, GrowlQuotation *quot,
     OPCODE1(CHOOSE);
     OPCODE1(CALL);
     OPCODE1(CALL_NEXT);
+    OPCODE1(PUSH_NEXT);
     OPCODE1(TAIL_CALL);
     OPCODE(WORD) {
       intptr_t idx;
       size_t bytes_read = growl_sleb128_peek(&quot->data[offset], &idx);
-      printf("WORD %s\n", vm->defs.data[idx].name);
+      fprintf(stderr, "WORD %s\n", vm->defs.data[idx].name);
       return offset + bytes_read;
     }
     OPCODE(TAIL_WORD) {
       intptr_t idx;
       size_t bytes_read = growl_sleb128_peek(&quot->data[offset], &idx);
-      printf("TAIL_WORD %s\n", vm->defs.data[idx].name);
+      fprintf(stderr, "TAIL_WORD %s\n", vm->defs.data[idx].name);
       return offset + bytes_read;
     }
     OPCODE1(RETURN);
     OPCODE1(COMPOSE);
     OPCODE1(CURRY);
+    OPCODE1(DIP);
     OPCODE1(PPRINT);
     OPCODE1(ADD);
     OPCODE1(MUL);

next/core/dynarray.h

@@ -0,0 +1,42 @@
+#ifndef GROWL_DYNARRAY_H
+#define GROWL_DYNARRAY_H
+
+// See https://nullprogram.com/blog/2023/10/05/
+
+#include <growl.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#define push(s, a)                                                             \
+  ({                                                                           \
+    typeof(s) s_ = (s);                                                        \
+    typeof(a) a_ = (a);                                                        \
+    if (s_->count >= s_->capacity) {                                           \
+      __grow(s_, sizeof(*s_->data), _Alignof(*s_->data), a_);                    \
+    }                                                                          \
+    s_->data + s_->count++;                                                    \
+  })
+
+static void __grow(void *slice, ptrdiff_t size, ptrdiff_t align, GrowlArena *a) {
+  struct {
+    uint8_t *data;
+    ptrdiff_t len;
+    ptrdiff_t cap;
+  } replica;
+  memcpy(&replica, slice, sizeof(replica));
+  if (!replica.data) {
+    replica.cap = 1;
+    replica.data = growl_arena_alloc(a, 2 * size, align, replica.cap);
+  } else if (a->free == replica.data + size * replica.cap) {
+    growl_arena_alloc(a, size, 1, replica.cap);
+  } else {
+    void *data = growl_arena_alloc(a, 2 * size, align, replica.cap);
+    memcpy(data, replica.data, size * replica.len);
+    replica.data = data;
+  }
+  replica.cap *= 2;
+  memcpy(slice, &replica, sizeof(replica));
+}
+
+#endif // GROWL_DYNARRAY_H

next/core/file.c

@@ -0,0 +1,49 @@
+#include <growl.h>
+
+static void file_finalize(void *data) {
+  FILE *f = data;
+  if (f && f != stdin && f != stdout && f != stderr)
+    fclose(f);
+}
+
+// clang-format off
+static GrowlAlienType alien_file_type = {
+  .name = "file",
+  .finalizer = file_finalize,
+  .call = NULL,
+};
+// clang-format on
+
+static Growl stdout_obj = GROWL_NIL;
+static void native_file_stdout(GrowlVM *vm) {
+  if (stdout_obj == GROWL_NIL) {
+    GrowlObjectHeader *hdr = growl_gc_alloc_tenured(
+        vm, sizeof(GrowlObjectHeader) + sizeof(GrowlAlien));
+    hdr->type = GROWL_TYPE_ALIEN;
+    GrowlAlien *stdout_alien = (GrowlAlien *)(hdr + 1);
+    stdout_alien->data = stdout;
+    stdout_alien->type = &alien_file_type;
+    stdout_obj = GROWL_BOX(hdr);
+  }
+  growl_push(vm, stdout_obj);
+}
+
+static void native_file_write(GrowlVM *vm) {
+  Growl file_obj = growl_pop(vm);
+  Growl string_obj = growl_pop(vm);
+
+  GrowlAlien *file_alien = growl_unwrap_alien(file_obj, &alien_file_type);
+  if (file_alien == NULL)
+    growl_vm_error(vm, "expected file object");
+
+  GrowlString *str = growl_unwrap_string(string_obj);
+  if (str == NULL)
+    growl_vm_error(vm, "expected string");
+
+  fwrite(str->data, sizeof(char), str->len, file_alien->data);
+}
+
+void growl_register_file_library(GrowlVM *vm) {
+  growl_register_native(vm, "file/stdout", native_file_stdout);
+  growl_register_native(vm, "file/write", native_file_write);
+}

next/core/gc.c

@@ -139,14 +139,26 @@ void growl_gc_collect(GrowlVM *vm) {
   gc_print_stats(vm, "before GC");
 #endif
 
+  // Forward work stack
   for (size_t i = 0; i < GROWL_STACK_SIZE; ++i) {
     vm->wst[i] = forward(vm, vm->wst[i]);
   }
 
+  // Forward retain stack
+  for (size_t i = 0; i < GROWL_STACK_SIZE; ++i) {
+    vm->rst[i] = forward(vm, vm->rst[i]);
+  }
+
+  // Forward GC roots
   for (size_t i = 0; i < vm->root_count; ++i) {
     *vm->roots[i] = forward(vm, *vm->roots[i]);
   }
 
+  // Forward word definitions
+  for (size_t i = 0; i < vm->defs.count; ++i) {
+    vm->defs.data[i].callable = forward(vm, vm->defs.data[i].callable);
+  }
+
   uint8_t *tenured_scan = vm->tenured.start;
   while (tenured_scan < vm->tenured.free) {
     GrowlObjectHeader *hdr = (GrowlObjectHeader *)tenured_scan;

next/core/lexer.c

@@ -134,7 +134,7 @@ int growl_lexer_next(GrowlLexer *lexer) {
 
   switch (next) {
   case '\\':
-    for (; next != '\n'; next = getc_ws(lexer))
+    for (; next != '\n'; next = lexer_getc(lexer))
       ;
     return growl_lexer_next(lexer);
   case '(':

next/core/native.c

@@ -0,0 +1,29 @@
+#include <growl.h>
+#include <string.h>
+
+#include "dynarray.h"
+
+static void call_native(GrowlVM *vm, void *data) {
+  void (*fn)(GrowlVM *) = data;
+  fn(vm);
+}
+
+// clang-format off
+static GrowlAlienType native_type = {
+  .name = "native",
+  .finalizer = NULL,
+  .call = call_native,
+};
+// clang-format on
+
+void growl_register_native(GrowlVM *vm, const char *name,
+                           void (*fn)(GrowlVM *)) {
+  Growl alien = growl_make_alien_tenured(vm, &native_type, (void *)fn);
+  GrowlDictionary *entry =
+      growl_dictionary_upsert(&vm->dictionary, name, &vm->arena);
+  GrowlDefinition *def = push(&vm->defs, &vm->arena);
+  def->name = growl_arena_strdup(&vm->arena, name);
+  def->callable = alien;
+  entry->callable = alien;
+  entry->index = vm->defs.count - 1;
+}

next/core/opcodes.h

@@ -5,6 +5,7 @@ enum GrowlOpcode {
   GOP_NOP = 0,
   GOP_PUSH_NIL,
   GOP_PUSH_CONSTANT,
+  GOP_PUSH_NEXT,
   GOP_DROP,
   GOP_DUP,
   GOP_SWAP,
@@ -26,6 +27,7 @@ enum GrowlOpcode {
   GOP_RETURN,
   GOP_COMPOSE,
   GOP_CURRY,
+  GOP_DIP,
   GOP_PPRINT,
   GOP_ADD,
   GOP_MUL,
@@ -36,6 +38,8 @@ enum GrowlOpcode {
   GOP_BOR,
   GOP_BXOR,
   GOP_BNOT,
+  GOP_AND,
+  GOP_OR,
   GOP_EQ,
   GOP_NEQ,
   GOP_LT,

next/core/print.c

@@ -8,57 +8,56 @@ void growl_println(Growl value) {
   putchar('\n');
 }
 
-static void print_escaped(const char *data, size_t len) {
+static void print_escaped(FILE *file, const char *data, size_t len) {
-  putchar('"');
+  putc('"', file);
   for (size_t i = 0; i < len; ++i) {
     switch (data[i]) {
     case '\0':
-      putchar('\\');
+      putc('\\', file);
-      putchar('0');
+      putc('0', file);
       break;
     case '\t':
-      putchar('\\');
+      putc('\\', file);
-      putchar('t');
+      putc('t', file);
       break;
     case '\n':
-      putchar('\\');
+      putc('\\', file);
-      putchar('n');
+      putc('n', file);
       break;
     case '\r':
-      putchar('\\');
+      putc('\\', file);
-      putchar('r');
+      putc('r', file);
       break;
     case '\b':
-      putchar('\\');
+      putc('\\', file);
-      putchar('b');
+      putc('b', file);
       break;
     case '\v':
-      putchar('\\');
+      putc('\\', file);
-      putchar('v');
+      putc('v', file);
       break;
     case '\f':
-      putchar('\\');
+      putc('\\', file);
-      putchar('f');
+      putc('f', file);
       break;
     case '\x1b':
-      putchar('\\');
+      putc('\\', file);
-      putchar('e');
+      putc('e', file);
       break;
     case '\\':
-      putchar('\\');
+      putc('\\', file);
-      putchar('\\');
+      putc('\\', file);
       break;
     case '"':
-      putchar('\\');
+      putc('\\', file);
-      putchar('"');
+      putc('"', file);
       break;
     default:
-      putchar(data[i]);
+      putc(data[i], file);
       break;
-
     }
   }
-  putchar('"');
+  putc('"', file);
 }
 
 void growl_print_to(FILE *file, Growl value) {
@@ -71,7 +70,7 @@ void growl_print_to(FILE *file, Growl value) {
     switch (hdr->type) {
     case GROWL_TYPE_STRING: {
       GrowlString *str = (GrowlString *)(hdr + 1);
-      print_escaped(str->data, str->len);
+      print_escaped(file, str->data, str->len);
       break;
     }
     default:

next/core/string.c

@@ -23,6 +23,18 @@ Growl growl_wrap_string(GrowlVM *vm, const char *cstr) {
   return GROWL_BOX(hdr);
 }
 
+Growl growl_wrap_string_tenured(GrowlVM *vm, const char *cstr) {
+  size_t len = strlen(cstr);
+  size_t size = sizeof(GrowlObjectHeader) + sizeof(GrowlString) + len + 1;
+  GrowlObjectHeader *hdr = growl_gc_alloc_tenured(vm, size);
+  hdr->type = GROWL_TYPE_STRING;
+  GrowlString *str = (GrowlString *)(hdr + 1);
+  str->len = len;
+  memcpy(str->data, cstr, len);
+  str->data[len] = 0;
+  return GROWL_BOX(hdr);
+}
+
 GrowlString *growl_unwrap_string(Growl obj) {
   if (obj == 0 || GROWL_IMM(obj))
     return NULL;

next/core/vm.c

@@ -31,9 +31,17 @@ GrowlVM *growl_vm_init(void) {
   vm->root_count = 0;
   vm->root_capacity = 0;
 
-  static uint8_t trampoline_code[] = {GOP_CALL_NEXT};
+  static uint8_t compose_code[] = {GOP_CALL_NEXT};
-  Growl trampoline = growl_make_quotation(vm, trampoline_code, 1, NULL, 0);
+  Growl compose_tramp = growl_make_quotation(vm, compose_code, 1, NULL, 0);
-  vm->compose_trampoline = (GrowlQuotation *)(GROWL_UNBOX(trampoline) + 1);
+  vm->compose_trampoline = (GrowlQuotation *)(GROWL_UNBOX(compose_tramp) + 1);
+
+  static uint8_t return_code[] = {GOP_RETURN};
+  Growl return_tramp = growl_make_quotation(vm, return_code, 1, NULL, 0);
+  vm->return_trampoline = (GrowlQuotation *)(GROWL_UNBOX(return_tramp) + 1);
+
+  static uint8_t dip_code[] = {GOP_PUSH_NEXT, GOP_RETURN};
+  Growl dip_tramp = growl_make_quotation(vm, dip_code, 2, NULL, 0);
+  vm->dip_trampoline = (GrowlQuotation *)(GROWL_UNBOX(dip_tramp) + 1);
 
   return vm;
 }
@@ -49,8 +57,8 @@ void growl_vm_free(GrowlVM *vm) {
   free(vm);
 }
 
-__attribute__((format(printf, 2, 3))) static noreturn void
+__attribute__((format(printf, 2, 3))) noreturn void
-vm_error(GrowlVM *vm, const char *fmt, ...) {
+growl_vm_error(GrowlVM *vm, const char *fmt, ...) {
   va_list args;
   va_start(args, fmt);
   fprintf(stderr, "vm: ");
@@ -62,19 +70,19 @@ vm_error(GrowlVM *vm, const char *fmt, ...) {
 
 void growl_push(GrowlVM *vm, Growl obj) {
   if (vm->sp >= vm->wst + GROWL_STACK_SIZE)
-    vm_error(vm, "work stack overflow");
+    growl_vm_error(vm, "work stack overflow");
   *vm->sp++ = obj;
 }
 
 Growl growl_peek(GrowlVM *vm, size_t depth) {
   if (vm->sp <= vm->wst + depth)
-    vm_error(vm, "work stack underflow");
+    growl_vm_error(vm, "work stack underflow");
   return vm->sp[-(depth + 1)];
 }
 
 Growl growl_pop(GrowlVM *vm) {
   if (vm->sp <= vm->wst)
-    vm_error(vm, "work stack underflow");
+    growl_vm_error(vm, "work stack underflow");
   Growl obj = *--vm->sp;
   *vm->sp = GROWL_NIL;
   return obj;
@@ -82,13 +90,13 @@ Growl growl_pop(GrowlVM *vm) {
 
 void growl_rpush(GrowlVM *vm, Growl obj) {
   if (vm->rsp >= vm->rst + GROWL_STACK_SIZE)
-    vm_error(vm, "work stack overflow");
+    growl_vm_error(vm, "work stack overflow");
   *vm->rsp++ = obj;
 }
 
 Growl growl_rpop(GrowlVM *vm) {
   if (vm->rsp <= vm->rst)
-    vm_error(vm, "work stack underflow");
+    growl_vm_error(vm, "work stack underflow");
   Growl obj = *--vm->rsp;
   *vm->rsp = GROWL_NIL;
   return obj;
@@ -96,7 +104,7 @@ Growl growl_rpop(GrowlVM *vm) {
 
 static void callstack_push(GrowlVM *vm, GrowlQuotation *q, uint8_t *ip) {
   if (vm->csp >= vm->cst + GROWL_CALL_STACK_SIZE)
-    vm_error(vm, "call stack overflow");
+    growl_vm_error(vm, "call stack overflow");
   vm->csp->quot = q;
   vm->csp->ip = ip;
   vm->csp->next = GROWL_NIL;
@@ -105,11 +113,12 @@ static void callstack_push(GrowlVM *vm, GrowlQuotation *q, uint8_t *ip) {
 
 static GrowlFrame callstack_pop(GrowlVM *vm) {
   if (vm->csp <= vm->cst)
-    vm_error(vm, "call stack underflow");
+    growl_vm_error(vm, "call stack underflow");
   return *--vm->csp;
 }
 
-static inline void dispatch(GrowlVM *vm, Growl obj) {
+static inline void dispatch(GrowlVM *vm, Growl obj,
+                            int tail __attribute__((unused))) {
   for (;;) {
     switch (growl_type(obj)) {
     case GROWL_TYPE_QUOTATION: {
@@ -131,8 +140,28 @@ static inline void dispatch(GrowlVM *vm, Growl obj) {
       obj = c->callable;
       continue;
     }
+    case GROWL_TYPE_ALIEN: {
+      GrowlAlien *alien = (GrowlAlien *)(GROWL_UNBOX(obj) + 1);
+      if (alien->type && alien->type->call) {
+        alien->type->call(vm, alien->data);
+        // After calling a native function, we need to return to the caller
+        if (vm->csp != vm->cst) {
+          GrowlFrame frame = callstack_pop(vm);
+          vm->current_quotation = frame.quot;
+          vm->ip = frame.ip;
+          vm->next = frame.next;
+        } else {
+          // No frames on call stack, use return trampoline to exit
+          vm->current_quotation = vm->return_trampoline;
+          vm->ip = vm->return_trampoline->data;
+        }
+        return;
+      }
+      growl_vm_error(vm, "attempt to call non-callable alien");
+    }
     default:
-      vm_error(vm, "attempt to call non-callable");
+      growl_vm_error(vm, "attempt to call non-callable (type=%d)",
+                     growl_type(obj));
     }
   }
 }
@@ -171,13 +200,18 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
       if (idx >= 0 && (size_t)idx < constants->count) {
         growl_push(vm, constants->data[idx]);
       } else {
-        vm_error(vm, "constant index %" PRIdPTR " out of bounds", idx);
+        growl_vm_error(vm, "constant index %" PRIdPTR " out of bounds", idx);
       }
     } else {
-      vm_error(vm, "attempt to index nil constant table");
+      growl_vm_error(vm, "attempt to index nil constant table");
     }
     VM_NEXT();
   }
+  VM_OP(PUSH_NEXT) {
+    growl_push(vm, vm->next);
+    vm->next = GROWL_NIL;
+    VM_NEXT();
+  }
   VM_OP(DROP) {
     (void)growl_pop(vm);
     VM_NEXT();
@@ -251,9 +285,9 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     VM_NEXT();
   }
   VM_OP(CHOOSE) {
-    Growl cond = growl_pop(vm);
     Growl f = growl_pop(vm);
     Growl t = growl_pop(vm);
+    Growl cond = growl_pop(vm);
     if (cond != GROWL_NIL) {
       growl_push(vm, t);
     } else {
@@ -264,32 +298,33 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
   VM_OP(CALL) {
     Growl obj = growl_pop(vm);
     callstack_push(vm, vm->current_quotation, vm->ip);
-    dispatch(vm, obj);
+    dispatch(vm, obj, 0);
     VM_NEXT();
   }
   VM_OP(CALL_NEXT) {
-    growl_push(vm, vm->compose_next);
+    Growl callable = vm->next;
-    vm->compose_next = GROWL_NIL;
+    vm->next = GROWL_NIL;
-    __attribute__((__fallthrough__));
+    dispatch(vm, callable, 1);
+    VM_NEXT();
   }
   VM_OP(TAIL_CALL) {
     Growl obj = growl_pop(vm);
-    dispatch(vm, obj);
+    dispatch(vm, obj, 1);
     VM_NEXT();
   }
   VM_OP(WORD) {
     intptr_t idx = growl_sleb128_decode(&vm->ip);
     GrowlDefinition *def = &vm->defs.data[idx];
-    Growl word = GROWL_BOX((GrowlObjectHeader *)(def->quotation) - 1);
+    Growl word = def->callable;
     callstack_push(vm, vm->current_quotation, vm->ip);
-    dispatch(vm, word);
+    dispatch(vm, word, 0);
     VM_NEXT();
   }
   VM_OP(TAIL_WORD) {
     intptr_t idx = growl_sleb128_decode(&vm->ip);
     GrowlDefinition *def = &vm->defs.data[idx];
-    Growl word = GROWL_BOX((GrowlObjectHeader *)(def->quotation) - 1);
+    Growl word = def->callable;
-    dispatch(vm, word);
+    dispatch(vm, word, 1);
     VM_NEXT();
   }
   VM_OP(RETURN) {
@@ -297,7 +332,7 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
       GrowlFrame frame = callstack_pop(vm);
       vm->current_quotation = frame.quot;
       vm->ip = frame.ip;
-      vm->compose_next = frame.next;
+      vm->next = frame.next;
     } else {
       goto done;
     }
@@ -308,7 +343,7 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     Growl first = growl_pop(vm);
     Growl composed = growl_compose(vm, first, second);
     if (composed == GROWL_NIL)
-      vm_error(vm, "attempt to compose with a non-callable");
+      growl_vm_error(vm, "attempt to compose with a non-callable");
     growl_push(vm, composed);
     VM_NEXT();
   }
@@ -317,10 +352,19 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     Growl value = growl_pop(vm);
     Growl curried = growl_curry(vm, value, callable);
     if (curried == GROWL_NIL)
-      vm_error(vm, "attempt to curry with a non-callable");
+      growl_vm_error(vm, "attempt to curry with a non-callable");
     growl_push(vm, curried);
     VM_NEXT();
   }
+  VM_OP(DIP) {
+    Growl callable = growl_pop(vm);
+    Growl x = growl_pop(vm);
+    callstack_push(vm, vm->current_quotation, vm->ip);
+    callstack_push(vm, vm->dip_trampoline, vm->dip_trampoline->data);
+    vm->csp[-1].next = x;
+    dispatch(vm, callable, 0);
+    VM_NEXT();
+  }
   VM_OP(PPRINT) {
     growl_println(growl_pop(vm));
     VM_NEXT();
@@ -333,7 +377,7 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     if (GROWL_IMM(b) && GROWL_IMM(a)) {                                        \
       growl_push(vm, GROWL_NUM(GROWL_ORD(a) op GROWL_ORD(b)));                 \
     } else {                                                                   \
-      vm_error(vm, "numeric op on non-numbers");                               \
+      growl_vm_error(vm, "numeric op on non-numbers");                         \
     }                                                                          \
     VM_NEXT();                                                                 \
   }
@@ -346,10 +390,10 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     Growl a = growl_pop(vm);
     if (GROWL_IMM(b) && GROWL_IMM(a)) {
       if (GROWL_ORD(b) == 0)
-        vm_error(vm, "division by zero");
+        growl_vm_error(vm, "division by zero");
       growl_push(vm, GROWL_NUM(GROWL_ORD(a) / GROWL_ORD(b)));
     } else {
-      vm_error(vm, "numeric op on non-numbers");
+      growl_vm_error(vm, "numeric op on non-numbers");
     };
     VM_NEXT();
   }
@@ -358,10 +402,10 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     Growl a = growl_pop(vm);
     if (GROWL_IMM(b) && GROWL_IMM(a)) {
       if (GROWL_ORD(b) == 0)
-        vm_error(vm, "division by zero");
+        growl_vm_error(vm, "division by zero");
       growl_push(vm, GROWL_NUM(GROWL_ORD(a) % GROWL_ORD(b)));
     } else {
-      vm_error(vm, "numeric op on non-numbers");
+      growl_vm_error(vm, "numeric op on non-numbers");
     };
     VM_NEXT();
   }
@@ -373,7 +417,27 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     if (GROWL_IMM(a)) {
       growl_push(vm, GROWL_NUM(~GROWL_ORD(a)));
     } else {
-      vm_error(vm, "arithmetic on non-numbers");
+      growl_vm_error(vm, "arithmetic on non-numbers");
+    }
+    VM_NEXT();
+  }
+  VM_OP(AND) {
+    Growl b = growl_pop(vm);
+    Growl a = growl_pop(vm);
+    if (a == GROWL_NIL) {
+      growl_push(vm, a);
+    } else {
+      growl_push(vm, b);
+    }
+    VM_NEXT();
+  }
+  VM_OP(OR) {
+    Growl b = growl_pop(vm);
+    Growl a = growl_pop(vm);
+    if (a == GROWL_NIL) {
+      growl_push(vm, b);
+    } else {
+      growl_push(vm, a);
     }
     VM_NEXT();
   }
@@ -399,7 +463,29 @@ int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot) {
     }
     VM_NEXT();
   }
-  VM_DEFAULT() { vm_error(vm, "unknown opcode %d", opcode); }
+
+#define VM_CMPOP(name, op)                                                     \
+  case GOP_##name: {                                                           \
+    Growl b = growl_pop(vm);                                                   \
+    Growl a = growl_pop(vm);                                                   \
+    if (GROWL_IMM(b) && GROWL_IMM(a)) {                                        \
+      if (GROWL_ORD(a) op GROWL_ORD(b)) {                                      \
+        growl_push(vm, GROWL_NUM(1));                                          \
+      } else {                                                                 \
+        growl_push(vm, GROWL_NIL);                                             \
+      }                                                                        \
+    } else {                                                                   \
+      growl_vm_error(vm, "comparison on non-numbers");                         \
+    }                                                                          \
+    VM_NEXT();                                                                 \
+  }
+
+  VM_CMPOP(LT, <);
+  VM_CMPOP(LTE, <=);
+  VM_CMPOP(GT, >);
+  VM_CMPOP(GTE, >=);
+
+  VM_DEFAULT() { growl_vm_error(vm, "unknown opcode %d", opcode); }
   VM_END()
 
 done:

next/include/growl.h

@@ -5,6 +5,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <stdnoreturn.h>
 
 typedef uintptr_t Growl;
 
@@ -28,6 +29,8 @@ typedef struct GrowlAlien GrowlAlien;
 typedef struct GrowlLexer GrowlLexer;
 typedef struct GrowlArena GrowlArena;
 typedef struct GrowlFrame GrowlFrame;
+typedef struct GrowlModule GrowlModule;
+typedef struct GrowlCompileContext GrowlCompileContext;
 typedef struct GrowlDictionary GrowlDictionary;
 typedef struct GrowlDefinition GrowlDefinition;
 typedef struct GrowlDefinitionTable GrowlDefinitionTable;
@@ -52,6 +55,8 @@ struct GrowlObjectHeader {
 };
 
 uint32_t growl_type(Growl obj);
+int growl_equals(Growl a, Growl b);
+
 uint64_t growl_hash_combine(uint64_t a, uint64_t b);
 uint64_t growl_hash_bytes(const uint8_t *data, size_t len);
 uint64_t growl_hash(Growl obj);
@@ -60,8 +65,6 @@ void growl_print_to(FILE *file, Growl value);
 void growl_print(Growl value);
 void growl_println(Growl value);
 
-int growl_equals(Growl a, Growl b);
-
 struct GrowlString {
   size_t len;
   char data[];
@@ -69,6 +72,7 @@ struct GrowlString {
 
 Growl growl_make_string(GrowlVM *vm, size_t len);
 Growl growl_wrap_string(GrowlVM *vm, const char *cstr);
+Growl growl_wrap_string_tenured(GrowlVM *vm, const char *cstr);
 GrowlString *growl_unwrap_string(Growl obj);
 
 struct GrowlList {
@@ -85,7 +89,6 @@ GrowlTuple *growl_unwrap_tuple(Growl obj);
 struct GrowlTable {};
 
 GrowlTable *growl_unwrap_table(Growl obj);
-GrowlTable *growl_table_upsert(GrowlVM *vm, GrowlTable **table, Growl key);
 
 struct GrowlQuotation {
   size_t count;
@@ -112,6 +115,7 @@ GrowlCurry *growl_unwrap_curry(Growl obj);
 
 struct GrowlAlienType {
   const char *name;
+  void (*call)(GrowlVM *, void *);
   void (*finalizer)(void *);
 };
 
@@ -121,7 +125,10 @@ struct GrowlAlien {
 };
 
 Growl growl_make_alien(GrowlVM *vm, GrowlAlienType *type, void *data);
+Growl growl_make_alien_tenured(GrowlVM *vm, GrowlAlienType *type, void *data);
 GrowlAlien *growl_unwrap_alien(Growl obj, GrowlAlienType *type);
+void growl_register_native(GrowlVM *vm, const char *name,
+                           void (*fn)(GrowlVM *));
 
 /** Lexer */
 enum {
@@ -179,7 +186,7 @@ struct GrowlFrame {
 
 struct GrowlDefinition {
   const char *name;
-  GrowlQuotation *quotation;
+  Growl callable;
 };
 
 struct GrowlDefinitionTable {
@@ -190,10 +197,20 @@ struct GrowlDefinitionTable {
 struct GrowlDictionary {
   GrowlDictionary *child[4];
   const char *name;
-  GrowlQuotation *quotation;
+  Growl callable;
   size_t index;
 };
 
+struct GrowlModule {
+  char *resolved_path;
+  GrowlModule *next;
+};
+
+struct GrowlCompileContext {
+  GrowlCompileContext *parent;
+  const char *file_path, *file_dir;
+};
+
 GrowlDictionary *growl_dictionary_upsert(GrowlDictionary **dict,
                                          const char *name, GrowlArena *perm);
 
@@ -213,7 +230,9 @@ struct GrowlVM {
   GrowlFrame cst[GROWL_CALL_STACK_SIZE], *csp;
 
   GrowlQuotation *compose_trampoline;
-  Growl compose_next;
+  GrowlQuotation *return_trampoline;
+  GrowlQuotation *dip_trampoline;
+  Growl next;
 
   Growl **roots;
   size_t root_count, root_capacity;
@@ -229,10 +248,19 @@ void growl_gc_collect(GrowlVM *vm);
 void growl_gc_root(GrowlVM *vm, Growl *ptr);
 size_t growl_gc_mark(GrowlVM *vm);
 void growl_gc_reset(GrowlVM *vm, size_t mark);
+void growl_push(GrowlVM *vm, Growl obj);
+Growl growl_peek(GrowlVM *vm, size_t depth);
+Growl growl_pop(GrowlVM *vm);
+void growl_rpush(GrowlVM *vm, Growl obj);
+Growl growl_rpop(GrowlVM *vm);
+noreturn void growl_vm_error(GrowlVM *vm, const char *fmt, ...);
 int growl_vm_execute(GrowlVM *vm, GrowlQuotation *quot);
 
 /** Compiler */
 Growl growl_compile(GrowlVM *vm, GrowlLexer *lexer);
 void growl_disassemble(GrowlVM *vm, GrowlQuotation *quot);
 
+/** Extra libraries */
+void growl_register_file_library(GrowlVM *vm);
+
 #endif // GROWL_H

next/main.c

@@ -1,24 +1,26 @@
-#include "core/opcodes.h"
 #include <growl.h>
+#include <math.h>
 
 int main(void) {
   GrowlVM *vm = growl_vm_init();
+  growl_register_file_library(vm);
   GrowlLexer lexer = {0};
   lexer.file = stdin;
 
   Growl obj = growl_compile(vm, &lexer);
   if (obj != GROWL_NIL) {
     GrowlQuotation *quot = growl_unwrap_quotation(obj);
-    growl_disassemble(vm, quot);
+    if (!growl_vm_execute(vm, quot)) {
-    growl_vm_execute(vm, quot);
+      if (vm->sp != vm->wst) {
-
+        fprintf(stderr, "Stack:");
-    printf("Stack:");
         for (Growl *p = vm->wst; p < vm->sp; p++) {
-      putchar(' ');
+          putc(' ', stderr);
-      growl_print(*p);
+          growl_print_to(stderr, *p);
         }
         putchar('\n');
       }
+    }
+  }
 
   growl_gc_collect(vm);
   growl_vm_free(vm);

std.grr

@@ -8,7 +8,6 @@ def eprintln { stderr fprint "\n" stderr fprint }
 def when { [] if }
 def unless { swap when }
 
-def dip { swap [] curry compose call }
 def 2dip { swap [dip] dip }
 def 3dip { swap [2dip] dip }