Make sure array slicing doesn't require a pointer and disallow automatic

stackifying of values

3 files changed, 35 insertions, 34 deletions

diff --git a/builtins/array.c b/builtins/array.c
index 2d45591c..4e8bf20c 100644
--- a/builtins/array.c
+++ b/builtins/array.c
@@ -261,54 +261,54 @@ public array_t Array$sample(array_t arr, int64_t n, array_t weights, const TypeI
     return selected;
 }
 
-public array_t Array$from(array_t *array, int64_t first)
+public array_t Array$from(array_t array, int64_t first)
 {
     if (first < 0)
-        first = array->length + first + 1;
+        first = array.length + first + 1;
 
-    if (first < 1 || first > array->length)
-        return (array_t){.atomic=array->atomic};
+    if (first < 1 || first > array.length)
+        return (array_t){.atomic=array.atomic};
 
     return (array_t){
-        .atomic=array->atomic,
-        .data=array->data + array->stride*(first-1),
-        .length=array->length - first + 1,
-        .stride=array->stride,
-        .data_refcount=array->data_refcount,
+        .atomic=array.atomic,
+        .data=array.data + array.stride*(first-1),
+        .length=array.length - first + 1,
+        .stride=array.stride,
+        .data_refcount=array.data_refcount,
     };
 }
 
-public array_t Array$to(array_t *array, int64_t last)
+public array_t Array$to(array_t array, int64_t last)
 {
     if (last < 0)
-        last = array->length + last + 1;
+        last = array.length + last + 1;
 
-    if (last > array->length)
-        last = array->length;
+    if (last > array.length)
+        last = array.length;
 
     if (last == 0)
-        return (array_t){.atomic=array->atomic};
+        return (array_t){.atomic=array.atomic};
 
     return (array_t){
-        .atomic=array->atomic,
-        .data=array->data,
+        .atomic=array.atomic,
+        .data=array.data,
         .length=last,
-        .stride=array->stride,
-        .data_refcount=array->data_refcount,
+        .stride=array.stride,
+        .data_refcount=array.data_refcount,
     };
 }
 
-public array_t Array$by(array_t *array, int64_t stride)
+public array_t Array$by(array_t array, int64_t stride)
 {
     if (stride == 0)
-        return (array_t){.atomic=array->atomic};
+        return (array_t){.atomic=array.atomic};
 
     return (array_t){
-        .atomic=array->atomic,
-        .data=(stride < 0 ? array->data + (array->stride * (array->length - 1)) : array->data),
-        .length=(stride < 0 ? array->length / -stride : array->length / stride) + ((array->length % stride) != 0),
-        .stride=array->stride * stride,
-        .data_refcount=array->data_refcount,
+        .atomic=array.atomic,
+        .data=(stride < 0 ? array.data + (array.stride * (array.length - 1)) : array.data),
+        .length=(stride < 0 ? array.length / -stride : array.length / stride) + ((array.length % stride) != 0),
+        .stride=array.stride * stride,
+        .data_refcount=array.data_refcount,
     };
 }
 
diff --git a/builtins/array.h b/builtins/array.h
index 56794a22..d60483db 100644
--- a/builtins/array.h
+++ b/builtins/array.h
@@ -64,9 +64,9 @@ array_t Array$sample(array_t arr, int64_t n, array_t weights, const TypeInfo *ty
 void Array$clear(array_t *array);
 void Array$compact(array_t *arr, const TypeInfo *type);
 bool Array$contains(array_t array, void *item, const TypeInfo *type);
-array_t Array$from(array_t *array, int64_t first);
-array_t Array$to(array_t *array, int64_t last);
-array_t Array$by(array_t *array, int64_t stride);
+array_t Array$from(array_t array, int64_t first);
+array_t Array$to(array_t array, int64_t last);
+array_t Array$by(array_t array, int64_t stride);
 array_t Array$reversed(array_t array);
 array_t Array$concat(array_t x, array_t y, const TypeInfo *type);
 uint32_t Array$hash(const array_t *arr, const TypeInfo *type);
diff --git a/compile.c b/compile.c
index dc6e3d78..0acbceb6 100644
--- a/compile.c
+++ b/compile.c
@@ -1083,7 +1083,7 @@ CORD compile_to_pointer_depth(env_t *env, ast_t *ast, int64_t target_depth, bool
             if (ast->tag == Var && target_depth == 1)
                 val = CORD_all("(&", val, ")");
             else
-                val = CORD_all("stack(", val, ")");
+                code_err(ast, "This should be a pointer, not %T", get_type(env, ast));
             t = Type(PointerType, .pointed=t, .is_stack=true);
             ++depth;
         } else {
@@ -1323,8 +1323,9 @@ CORD compile(env_t *env, ast_t *ast)
     case StackReference: {
         ast_t *subject = Match(ast, StackReference)->value;
         if (can_be_mutated(env, subject))
-            return CORD_all("(&", compile(env, subject), ")");
-        return CORD_all("stack(", compile(env, subject), ")");
+            return CORD_all("(&", compile_lvalue(env, subject), ")");
+        else
+            code_err(subject, "This subject can't be mutated!");
     }
     case Optional: {
         return compile(env, Match(ast, Optional)->value);
@@ -1910,15 +1911,15 @@ CORD compile(env_t *env, ast_t *ast)
                 (void)compile_arguments(env, ast, NULL, call->args);
                 return CORD_all("Array$clear(", self, ")");
             } else if (streq(call->name, "from")) {
-                CORD self = compile_to_pointer_depth(env, call->self, 1, false);
+                CORD self = compile_to_pointer_depth(env, call->self, 0, false);
                 arg_t *arg_spec = new(arg_t, .name="first", .type=Type(IntType, .bits=64));
                 return CORD_all("Array$from(", self, ", ", compile_arguments(env, ast, arg_spec, call->args), ")");
             } else if (streq(call->name, "to")) {
-                CORD self = compile_to_pointer_depth(env, call->self, 1, false);
+                CORD self = compile_to_pointer_depth(env, call->self, 0, false);
                 arg_t *arg_spec = new(arg_t, .name="last", .type=Type(IntType, .bits=64));
                 return CORD_all("Array$to(", self, ", ", compile_arguments(env, ast, arg_spec, call->args), ")");
             } else if (streq(call->name, "by")) {
-                CORD self = compile_to_pointer_depth(env, call->self, 1, false);
+                CORD self = compile_to_pointer_depth(env, call->self, 0, false);
                 arg_t *arg_spec = new(arg_t, .name="stride", .type=Type(IntType, .bits=64));
                 return CORD_all("Array$by(", self, ", ", compile_arguments(env, ast, arg_spec, call->args), ")");
             } else if (streq(call->name, "reversed")) {