Support :dynamic-defs dynamic binding

src/boot/boot.janet

@@ -3581,6 +3581,7 @@
                -e code : Execute a string of janet
                -E code arguments... : Evaluate  an expression as a short-fn with arguments
                -d : Set the debug flag in the REPL
+               -D : Use dynamic def bindings
                -r : Enter the REPL after running all scripts
                -R : Disables loading profile.janet when JANET_PROFILE is present
                -p : Keep on executing if there is a top-level error (persistent)
@@ -3631,6 +3632,7 @@
              (error (get thunk :error)))
            math/inf)
      "d" (fn [&] (set debug-flag true) 1)
+     "D" (fn [&] (setdyn :dynamic-defs true) 1)
      "w" (fn [i &] (set warn-level (get-lint-level i)) 2)
      "x" (fn [i &] (set error-level (get-lint-level i)) 2)
      "R" (fn [&] (setdyn :profilepath nil) 1)})

src/core/compile.c

@@ -238,12 +238,10 @@ JanetSlot janetc_resolve(
             case JANET_BINDING_DEF:
             case JANET_BINDING_MACRO: /* Macro should function like defs when not in calling pos */
                 ret = janetc_cslot(binding.value);
-                break;
-            case JANET_BINDING_DEF_REF:
-            case JANET_BINDING_MACRO_REF:
-                ret = janetc_cslot(binding.value);
-                ret.flags |= JANET_SLOT_REF | JANET_SLOT_NAMED | JANET_SLOTTYPE_ANY;
-                ret.flags &= ~JANET_SLOT_CONSTANT;
+                if (binding.dynamic) {
+                    ret.flags |= JANET_SLOT_REF | JANET_SLOT_NAMED | JANET_SLOTTYPE_ANY;
+                    ret.flags &= ~JANET_SLOT_CONSTANT;
+                }
                 break;
             case JANET_BINDING_VAR: {
                 ret = janetc_cslot(binding.value);
@@ -657,7 +655,7 @@ static int macroexpand1(
     }
     Janet macroval;
     JanetBindingType btype = janet_resolve(c->env, name, &macroval);
-    if (!(btype == JANET_BINDING_MACRO || btype == JANET_BINDING_MACRO_REF) ||
+    if (btype != JANET_BINDING_MACRO ||
             !janet_checktype(macroval, JANET_FUNCTION))
         return 0;
 

src/core/specials.c

@@ -331,8 +331,11 @@ static int defleaf(
         JanetTable *entry = janet_table_clone(tab);
         janet_table_put(entry, janet_ckeywordv("source-map"),
                         janet_wrap_tuple(janetc_make_sourcemap(c)));
+        if (janet_truthy(janet_dyn("dynamic-defs"))) {
+            janet_table_put(entry, janet_ckeywordv("dynamic"), janet_wrap_true());
+        }
 
-        if (!janet_checktype(janet_table_get(entry, janet_ckeywordv("redef")), JANET_NIL)) {
+        if (!janet_checktype(janet_table_get(entry, janet_ckeywordv("dynamic")), JANET_NIL)) {
             JanetBinding binding = janet_resolve_ext(c->env, sym);
             JanetArray *ref;
             if (janet_checktype(binding.value, JANET_ARRAY)) {
@@ -341,7 +344,7 @@ static int defleaf(
                 ref = janet_array(1);
                 janet_array_push(ref, janet_wrap_nil());
             }
-            janet_table_put(entry, janet_ckeywordv("ref"), janet_wrap_array(ref));
+            janet_table_put(entry, janet_ckeywordv("value"), janet_wrap_array(ref));
             JanetSlot refslot = janetc_cslot(janet_wrap_array(ref));
             janetc_emit_ssu(c, JOP_PUT_INDEX, refslot, s, 0, 0);
         } else {

src/core/util.c

@@ -604,7 +604,8 @@ JanetBinding janet_resolve_ext(JanetTable *env, const uint8_t *sym) {
     JanetBinding binding = {
         JANET_BINDING_NONE,
         janet_wrap_nil(),
-        JANET_BINDING_DEP_NONE
+        JANET_BINDING_DEP_NONE,
+        JANET_BINDING_STATIC
     };
 
     /* Check environment for entry */
@@ -627,37 +628,39 @@ JanetBinding janet_resolve_ext(JanetTable *env, const uint8_t *sym) {
         binding.deprecation = JANET_BINDING_DEP_NORMAL;
     }
 
-    ref = janet_table_get(entry_table, janet_ckeywordv("ref"));
-    int is_value = !janet_checktype(ref, JANET_ARRAY);
-    int is_macro = !janet_checktype(janet_table_get(entry_table, janet_ckeywordv("macro")), JANET_NIL);
-    int is_redef = !janet_checktype(janet_table_get(entry_table, janet_ckeywordv("redef")), JANET_NIL);
+    binding.dynamic = !janet_checktype(janet_table_get(entry_table, janet_ckeywordv("dynamic")), JANET_NIL);
 
-    if (is_redef && is_value) {
-        /* invalid, return empty binding */
-        return binding;
-    } else if (is_macro && is_redef) {
-        binding.value = ref;
-        binding.type = JANET_BINDING_MACRO_REF;
-    } else if (is_macro) {
+    if (!janet_checktype(
+                janet_table_get(entry_table, janet_ckeywordv("macro")),
+                JANET_NIL)) {
         binding.value = janet_table_get(entry_table, janet_ckeywordv("value"));
         binding.type = JANET_BINDING_MACRO;
-    } else if (is_redef) {
-        binding.value = ref;
-        binding.type = JANET_BINDING_DEF_REF;
-    } else if (is_value) {
-        binding.value = janet_table_get(entry_table, janet_ckeywordv("value"));
-        binding.type = JANET_BINDING_DEF;
-    } else {
-        binding.value = ref;
-        binding.type = JANET_BINDING_VAR;
+        return binding;
     }
 
+    ref = janet_table_get(entry_table, janet_ckeywordv("ref"));
+    if (janet_checktype(ref, JANET_ARRAY)) {
+        binding.value = ref;
+        binding.type = JANET_BINDING_VAR;
+        return binding;
+    }
+
+    binding.value = janet_table_get(entry_table, janet_ckeywordv("value"));
+    binding.type = JANET_BINDING_DEF;
     return binding;
 }
 
 JanetBindingType janet_resolve(JanetTable *env, const uint8_t *sym, Janet *out) {
     JanetBinding binding = janet_resolve_ext(env, sym);
-    *out = binding.value;
+    if (binding.dynamic) {
+        if (janet_checktype(binding.value, JANET_ARRAY)) {
+            *out = janet_array_peek(janet_unwrap_array(binding.value));
+        } else {
+            *out = janet_wrap_nil();
+        }
+    } else {
+        *out = binding.value;
+    }
     return binding.type;
 }
 

src/include/janet.h

@@ -1779,9 +1779,7 @@ typedef enum {
     JANET_BINDING_NONE,
     JANET_BINDING_DEF,
     JANET_BINDING_VAR,
-    JANET_BINDING_MACRO,
-    JANET_BINDING_DEF_REF,
-    JANET_BINDING_MACRO_REF
+    JANET_BINDING_MACRO
 } JanetBindingType;
 
 typedef struct {
@@ -1793,6 +1791,9 @@ typedef struct {
         JANET_BINDING_DEP_NORMAL,
         JANET_BINDING_DEP_STRICT,
     } deprecation;
+    enum {
+        JANET_BINDING_STATIC,
+        JANET_BINDING_DYNAMIC } dynamic;
 } JanetBinding;
 
 JANET_API void janet_def(JanetTable *env, const char *name, Janet val, const char *documentation);

test/suite0000.janet

@@ -295,18 +295,25 @@
     (++ i))
   (assert (= i 6) "when macro"))
 
-# Redefs
+# Dynamic defs
 
-(def noredef 0)
-(defn noredef-inc [] (+ 1 noredef))
-(assert (= 1 (noredef-inc)) "result before redef without :redef")
-(def noredef 1)
-(assert (= 1 (noredef-inc)) "result after redef without :redef")
-(def redef :redef 0)
-(defn redef-inc [] (+ 1 redef))
-(assert (= 1 (redef-inc)) "result before redef with :redef")
-(def redef :redef 1)
-(assert (= 2 (redef-inc)) "result before redef with :redef")
+(def staticdef 0)
+(defn staticdef-inc [] (+ 1 staticdef))
+(assert (= 1 (staticdef-inc)) "result before redefinition without :dynamic")
+(def staticdef 1)
+(assert (= 1 (staticdef-inc)) "result after redefinition without :dynamic")
+(def dynamicdef :dynamic 0)
+(defn dynamicdef-inc [] (+ 1 dynamicdef))
+(assert (= 1 (dynamicdef-inc)) "result before redefinition with :dynamic")
+(def dynamicdef :dynamic 1)
+(assert (= 2 (dynamicdef-inc)) "result after redefinition with :dynamic")
+(setdyn :dynamic-defs true)
+(def dynamicdef2 0)
+(defn dynamicdef2-inc [] (+ 1 dynamicdef2))
+(assert (= 1 (dynamicdef2-inc)) "result before redefinition with :dynamic-defs")
+(def dynamicdef2 1)
+(assert (= 2 (dynamicdef2-inc)) "result after redefinition with :dynamic-defs")
+(setdyn :dynamic-defs nil)
 
 # Denormal tables and structs