X-Git-Url: https://git.saurik.com/cycript.git/blobdiff_plain/e23a907053d46f6db4b3123316ef8d671fb3714a..ca52e3a3a95947a04788d3fce01d8d856e5f1544:/ObjectiveC/Library.mm?ds=sidebyside

diff --git a/ObjectiveC/Library.mm b/ObjectiveC/Library.mm
index e3b8917..7b62f70 100644
--- a/ObjectiveC/Library.mm
+++ b/ObjectiveC/Library.mm
@@ -1,28 +1,24 @@
 /* Cycript - Optimizing JavaScript Compiler/Runtime
- * Copyright (C) 2009-2012  Jay Freeman (saurik)
+ * Copyright (C) 2009-2013  Jay Freeman (saurik)
 */
 
-/* GNU Lesser General Public License, Version 3 {{{ */
+/* GNU General Public License, Version 3 {{{ */
 /*
- * Cycript is free software: you can redistribute it and/or modify it under
- * the terms of the GNU Lesser General Public License as published by the
- * Free Software Foundation, either version 3 of the License, or (at your
- * option) any later version.
+ * Cycript is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation, either version 3 of the License,
+ * or (at your option) any later version.
  *
- * Cycript is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
- * License for more details.
+ * Cycript is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
  *
- * You should have received a copy of the GNU Lesser General Public License
+ * You should have received a copy of the GNU General Public License
  * along with Cycript.  If not, see <http://www.gnu.org/licenses/>.
 **/
 /* }}} */
 
-#ifdef __APPLE__
-#include "Struct.hpp"
-#endif
-
 #include <Foundation/Foundation.h>
 
 #include "ObjectiveC/Internal.hpp"
@@ -36,10 +32,14 @@
 #ifdef __APPLE__
 #include <CoreFoundation/CoreFoundation.h>
 #include <JavaScriptCore/JSStringRefCF.h>
-#include <WebKit/WebScriptObject.h>
 #include <objc/runtime.h>
 #endif
 
+#ifdef __APPLE__
+#include <malloc/malloc.h>
+#include <mach/mach.h>
+#endif
+
 #include "Error.hpp"
 #include "JavaScript.hpp"
 #include "String.hpp"
@@ -47,17 +47,18 @@
 
 #include <cmath>
 #include <map>
+#include <set>
 
 #include <dlfcn.h>
 
-#define CYObjectiveTry_(context) { \
-    JSContextRef context_(context); \
+#define CYObjectiveTry_ { \
     try
 #define CYObjectiveTry { \
+    JSContextRef context(context_); \
     try
 #define CYObjectiveCatch \
     catch (const CYException &error) { \
-        @throw CYCastNSObject(NULL, context_, error.CastJSValue(context_)); \
+        @throw CYCastNSObject(NULL, context, error.CastJSValue(context)); \
     } \
 }
 
@@ -128,42 +129,72 @@ static void (*$objc_setAssociatedObject)(id object, void *key, id value, objc_As
 static id (*$objc_getAssociatedObject)(id object, void *key);
 static void (*$objc_removeAssociatedObjects)(id object);
 
-JSValueRef CYSendMessage(apr_pool_t *pool, JSContextRef context, id self, Class super, SEL _cmd, size_t count, const JSValueRef arguments[], bool initialize, JSValueRef *exception);
+struct BlockLiteral {
+    Class isa;
+    int flags;
+    int reserved;
+    void (*invoke)(void *, ...);
+    void *descriptor;
+};
+
+struct BlockDescriptor1 {
+    unsigned long int reserved;
+    unsigned long int size;
+};
+
+struct BlockDescriptor2 {
+    void (*copy_helper)(BlockLiteral *dst, BlockLiteral *src);
+    void (*dispose_helper)(BlockLiteral *src);
+};
+
+struct BlockDescriptor3 {
+    const char *signature;
+    const char *layout;
+};
+
+enum {
+    BLOCK_DEALLOCATING = 0x0001,
+    BLOCK_REFCOUNT_MASK = 0xfffe,
+    BLOCK_NEEDS_FREE = 1 << 24,
+    BLOCK_HAS_COPY_DISPOSE = 1 << 25,
+    BLOCK_HAS_CTOR = 1 << 26,
+    BLOCK_IS_GC = 1 << 27,
+    BLOCK_IS_GLOBAL = 1 << 28,
+    BLOCK_HAS_STRET = 1 << 29,
+    BLOCK_HAS_SIGNATURE = 1 << 30,
+};
+
+JSValueRef CYSendMessage(CYPool &pool, JSContextRef context, id self, Class super, SEL _cmd, size_t count, const JSValueRef arguments[], bool initialize);
 
 /* Objective-C Pool Release {{{ */
-apr_status_t CYPoolRelease_(void *data) {
+void CYPoolRelease_(void *data) {
     id object(reinterpret_cast<id>(data));
     [object release];
-    return APR_SUCCESS;
 }
 
-id CYPoolRelease_(apr_pool_t *pool, id object) {
+id CYPoolRelease_(CYPool *pool, id object) {
     if (object == nil)
         return nil;
     else if (pool == NULL)
         return [object autorelease];
     else {
-        apr_pool_cleanup_register(pool, object, &CYPoolRelease_, &apr_pool_cleanup_null);
+        pool->atexit(CYPoolRelease_);
         return object;
     }
 }
 
 template <typename Type_>
-Type_ CYPoolRelease(apr_pool_t *pool, Type_ object) {
+Type_ CYPoolRelease(CYPool *pool, Type_ object) {
     return (Type_) CYPoolRelease_(pool, (id) object);
 }
 /* }}} */
 /* Objective-C Strings {{{ */
-const char *CYPoolCString(apr_pool_t *pool, JSContextRef context, NSString *value) {
-    if (pool == NULL)
-        return [value UTF8String];
-    else {
-        size_t size([value maximumLengthOfBytesUsingEncoding:NSUTF8StringEncoding] + 1);
-        char *string(new(pool) char[size]);
-        if (![value getCString:string maxLength:size encoding:NSUTF8StringEncoding])
-            throw CYJSError(context, "[NSString getCString:maxLength:encoding:] == NO");
-        return string;
-    }
+const char *CYPoolCString(CYPool &pool, JSContextRef context, NSString *value) {
+    size_t size([value maximumLengthOfBytesUsingEncoding:NSUTF8StringEncoding] + 1);
+    char *string(new(pool) char[size]);
+    if (![value getCString:string maxLength:size encoding:NSUTF8StringEncoding])
+        throw CYJSError(context, "[NSString getCString:maxLength:encoding:] == NO");
+    return string;
 }
 
 JSStringRef CYCopyJSString(JSContextRef context, NSString *value) {
@@ -204,16 +235,16 @@ NSString *CYCopyNSString(JSContextRef context, JSValueRef value) {
     return CYCopyNSString(context, CYJSString(context, value));
 }
 
-NSString *CYCastNSString(apr_pool_t *pool, const CYUTF8String &value) {
+NSString *CYCastNSString(CYPool *pool, const CYUTF8String &value) {
     return CYPoolRelease(pool, CYCopyNSString(value));
 }
 
-NSString *CYCastNSString(apr_pool_t *pool, SEL sel) {
+NSString *CYCastNSString(CYPool *pool, SEL sel) {
     const char *name(sel_getName(sel));
     return CYPoolRelease(pool, CYCopyNSString(CYUTF8String(name, strlen(name))));
 }
 
-NSString *CYCastNSString(apr_pool_t *pool, JSContextRef context, JSStringRef value) {
+NSString *CYCastNSString(CYPool *pool, JSContextRef context, JSStringRef value) {
     return CYPoolRelease(pool, CYCopyNSString(context, value));
 }
 
@@ -235,7 +266,7 @@ size_t CYGetIndex(NSString *value) {
     return CYGetIndex(CYCastUTF8String(value));
 }
 
-bool CYGetOffset(apr_pool_t *pool, JSContextRef context, NSString *value, ssize_t &index) {
+bool CYGetOffset(CYPool &pool, JSContextRef context, NSString *value, ssize_t &index) {
     return CYGetOffset(CYPoolCString(pool, context, value), index);
 }
 
@@ -246,6 +277,7 @@ static JSClassRef FunctionInstance_;
 static JSClassRef ObjectInstance_;
 static JSClassRef StringInstance_;
 
+static JSClassRef Class_;
 static JSClassRef Internal_;
 static JSClassRef Message_;
 static JSClassRef Messages_;
@@ -265,8 +297,9 @@ static JSClassRef ObjectiveC_Images_;
 static Class NSCFBoolean_;
 static Class NSCFType_;
 static Class NSGenericDeallocHandler_;
-static Class NSMessageBuilder_;
 static Class NSZombie_;
+
+static std::set<Class> banned_;
 #else
 static Class NSBoolNumber_;
 #endif
@@ -290,9 +323,11 @@ Type_privateData *Selector_privateData::GetType() const {
 
 static JSValueRef Instance_callAsFunction_toString(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception);
 
-JSValueRef CYGetClassPrototype(JSContextRef context, id self) {
+JSValueRef CYGetClassPrototype(JSContextRef context, Class self, bool meta) {
     if (self == nil)
         return CYGetCachedObject(context, CYJSString("Instance_prototype"));
+    else if (meta && !class_isMetaClass(self))
+        return CYGetCachedObject(context, CYJSString("Class_prototype"));
 
     JSObjectRef global(CYGetGlobalObject(context));
     JSObjectRef cy(CYCastJSObject(context, CYGetProperty(context, global, cy_s)));
@@ -317,7 +352,7 @@ JSValueRef CYGetClassPrototype(JSContextRef context, id self) {
     else if (self == NSString_)
         prototype = CYGetCachedObject(context, CYJSString("StringInstance_prototype"));
     else
-        prototype = CYGetClassPrototype(context, class_getSuperclass(self));
+        prototype = CYGetClassPrototype(context, class_getSuperclass(self), meta);
 
     JSObjectRef object(JSObjectMake(context, _class, NULL));
     JSObjectSetPrototype(context, object, prototype);
@@ -326,14 +361,14 @@ JSValueRef CYGetClassPrototype(JSContextRef context, id self) {
     return object;
 }
 
-JSObjectRef Messages::Make(JSContextRef context, Class _class, bool array) {
+_finline JSValueRef CYGetClassPrototype(JSContextRef context, Class self) {
+    return CYGetClassPrototype(context, self, class_isMetaClass(self));
+}
+
+JSObjectRef Messages::Make(JSContextRef context, Class _class) {
     JSObjectRef value(JSObjectMake(context, Messages_, new Messages(_class)));
-    if (_class == NSArray_)
-        array = true;
     if (Class super = class_getSuperclass(_class))
-        JSObjectSetPrototype(context, value, Messages::Make(context, super, array));
-    /*else if (array)
-        JSObjectSetPrototype(context, value, Array_prototype_);*/
+        JSObjectSetPrototype(context, value, Messages::Make(context, super));
     return value;
 }
 
@@ -399,6 +434,7 @@ JSObjectRef CYMakeInstance(JSContextRef context, id object, bool transient) {
 
 - (bool) cy$hasProperty:(NSString *)name;
 - (NSObject *) cy$getProperty:(NSString *)name;
+- (JSValueRef) cy$getProperty:(NSString *)name inContext:(JSContextRef)context;
 - (bool) cy$setProperty:(NSString *)name to:(NSObject *)value;
 - (bool) cy$deleteProperty:(NSString *)name;
 - (void) cy$getPropertyNames:(JSPropertyNameAccumulatorRef)names inContext:(JSContextRef)context;
@@ -435,7 +471,7 @@ NSString *CYCastNSCYON(id value, bool objective) {
             else if (_class == NSZombie_)
                 string = [NSString stringWithFormat:@"<_NSZombie_: %p>", value];
             // XXX: frowny /in/ the pants
-            else if (value == NSGenericDeallocHandler_ || value == NSMessageBuilder_ || value == Object_)
+            else if (banned_.find(value) != banned_.end())
                 string = nil;
 #endif
             else
@@ -484,7 +520,9 @@ struct PropertyAttributes {
         name = property_getName(property);
         const char *attributes(property_getAttributes(property));
 
-        for (char *state, *token(apr_strtok(apr_pstrdup(pool_, attributes), ",", &state)); token != NULL; token = apr_strtok(NULL, ",", &state)) {
+        for (char *token(pool_.strdup(attributes)), *next; token != NULL; token = next) {
+            if ((next = strchr(token, ',')) != NULL)
+                *next++ = '\0';
             switch (*token) {
                 case 'R': readonly = true; break;
                 case 'C': copy = true; break;
@@ -509,7 +547,7 @@ struct PropertyAttributes {
 
     const char *Getter() {
         if (getter_ == NULL)
-            getter_ = apr_pstrdup(pool_, name);
+            getter_ = pool_.strdup(name);
         return getter_;
     }
 
@@ -538,7 +576,6 @@ struct PropertyAttributes {
 };
 #endif
 
-#ifndef __APPLE__
 @interface CYWebUndefined : NSObject {
 }
 
@@ -556,7 +593,6 @@ struct PropertyAttributes {
 @end
 
 #define WebUndefined CYWebUndefined
-#endif
 
 /* Bridge: CYJSObject {{{ */
 @interface CYJSObject : NSMutableDictionary {
@@ -594,20 +630,53 @@ struct PropertyAttributes {
 @end
 /* }}} */
 
+_finline bool CYJSValueIsNSObject(JSContextRef context, JSValueRef value) {
+    return JSValueIsObjectOfClass(context, value, Instance_);
+}
+
 _finline bool CYJSValueIsInstanceOfCachedConstructor(JSContextRef context, JSValueRef value, JSStringRef cache) {
-    JSValueRef exception(NULL);
-    JSObjectRef constructor(CYGetCachedObject(context, cache));
-    bool is(JSValueIsInstanceOfConstructor(context, value, constructor, &exception));
-    CYThrow(context, exception);
-    return is;
+    return _jsccall(JSValueIsInstanceOfConstructor, context, value, CYGetCachedObject(context, cache));
 }
 
-NSObject *CYCastNSObject(apr_pool_t *pool, JSContextRef context, JSObjectRef object) {
-    if (JSValueIsObjectOfClass(context, object, Instance_)) {
+NSObject *CYMakeBlock(void (*invoke)(), sig::Signature &signature) {
+    BlockLiteral *literal(reinterpret_cast<BlockLiteral *>(malloc(sizeof(BlockLiteral))));
+
+    struct Descriptor {
+        struct {
+            BlockDescriptor1 one_;
+            BlockDescriptor2 two_;
+            BlockDescriptor3 three_;
+        } d_;
+
+        CYPool pool_;
+    };
+
+    Descriptor *descriptor(new Descriptor);
+    memset(&descriptor->d_, 0, sizeof(descriptor->d_));
+
+    literal->isa = objc_getClass("__NSGlobalBlock__");
+    literal->flags = BLOCK_HAS_SIGNATURE | BLOCK_HAS_COPY_DISPOSE | BLOCK_IS_GLOBAL;
+    literal->reserved = 0;
+    literal->invoke = reinterpret_cast<void (*)(void *, ...)>(invoke);
+    literal->descriptor = descriptor;
+
+    descriptor->d_.one_.size = sizeof(descriptor->d_);
+    descriptor->d_.three_.signature = sig::Unparse(descriptor->pool_, &signature);
+
+    return reinterpret_cast<NSObject *>(literal);
+}
+
+NSObject *CYCastNSObject(CYPool *pool, JSContextRef context, JSObjectRef object) {
+    if (CYJSValueIsNSObject(context, object)) {
         Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
         return internal->GetValue();
     }
 
+    if (JSValueIsObjectOfClass(context, object, Functor_)) {
+        cy::Functor *internal(reinterpret_cast<cy::Functor *>(JSObjectGetPrivate(object)));
+        return CYMakeBlock(internal->GetValue(), internal->signature_);
+    }
+
     bool array(CYJSValueIsInstanceOfCachedConstructor(context, object, Array_s));
     id value(array ? [CYJSArray alloc] : [CYJSObject alloc]);
     return CYPoolRelease(pool, [value initWithJSObject:object inContext:context]);
@@ -623,7 +692,7 @@ NSNumber *CYCopyNSNumber(JSContextRef context, JSValueRef value) {
 @end
 #endif
 
-id CYNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef value, bool cast) {
+id CYNSObject(CYPool *pool, JSContextRef context, JSValueRef value, bool cast) {
     id object;
     bool copy;
 
@@ -676,12 +745,12 @@ id CYNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef value, bool cas
         return [object retain];
 }
 
-NSObject *CYCastNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef value) {
+NSObject *CYCastNSObject(CYPool *pool, JSContextRef context, JSValueRef value) {
     return CYNSObject(pool, context, value, true);
 }
 
-NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef value) {
-    return CYNSObject(pool, context, value, false);
+NSObject *CYCopyNSObject(CYPool &pool, JSContextRef context, JSValueRef value) {
+    return CYNSObject(&pool, context, value, false);
 }
 
 /* Bridge: NSArray {{{ */
@@ -730,15 +799,6 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
 }
 
 - (NSObject *) cy$getProperty:(NSString *)name {
-    if ([name isEqualToString:@"length"]) {
-        NSUInteger count([self count]);
-#ifdef __APPLE__
-        return [NSNumber numberWithUnsignedInteger:count];
-#else
-        return [NSNumber numberWithUnsignedInt:count];
-#endif
-    }
-
     size_t index(CYGetIndex(name));
     if (index == _not(size_t) || index >= [self count])
         return [super cy$getProperty:name];
@@ -746,6 +806,15 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
         return [self objectAtIndex:index];
 }
 
+- (JSValueRef) cy$getProperty:(NSString *)name inContext:(JSContextRef)context {
+    CYObjectiveTry_ {
+        if ([name isEqualToString:@"length"])
+            return CYCastJSValue(context, [self count]);
+    } CYObjectiveCatch
+
+    return [super cy$getProperty:name inContext:context];
+}
+
 - (void) cy$getPropertyNames:(JSPropertyNameAccumulatorRef)names inContext:(JSContextRef)context {
     [super cy$getPropertyNames:names inContext:context];
 
@@ -785,7 +854,7 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return objective ? value : [NSString stringWithFormat:@"@%@", value];
 }
 
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return CYCastJSValue(context, (bool) [self boolValue]);
 } CYObjectiveCatch }
 
@@ -942,7 +1011,7 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return objective ? value : [NSString stringWithFormat:@"@%@", value];
 }
 
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return [self cy$JSType] != kJSTypeBoolean ? CYCastJSValue(context, [self doubleValue]) : CYCastJSValue(context, static_cast<bool>([self boolValue]));
 } CYObjectiveCatch }
 
@@ -960,7 +1029,7 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return objective ? value : [NSString stringWithFormat:@"@%@", value];
 }
 
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return CYJSNull(context);
 } CYObjectiveCatch }
 
@@ -977,7 +1046,7 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return [self cy$valueOfInContext:context];
 }
 
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return NULL;
 } CYObjectiveCatch }
 
@@ -997,6 +1066,12 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return nil;
 }
 
+- (JSValueRef) cy$getProperty:(NSString *)name inContext:(JSContextRef)context { CYObjectiveTry_ {
+    if (NSObject *value = [self cy$getProperty:name])
+        return CYCastJSValue(context, value);
+    return NULL;
+} CYObjectiveCatch }
+
 - (bool) cy$setProperty:(NSString *)name to:(NSObject *)value {
     return false;
 }
@@ -1045,9 +1120,6 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
 }
 
 - (bool) cy$hasProperty:(NSString *)name {
-    if ([name isEqualToString:@"length"])
-        return true;
-
     size_t index(CYGetIndex(name));
     if (index == _not(size_t) || index >= [self length])
         return [super cy$hasProperty:name];
@@ -1056,15 +1128,6 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
 }
 
 - (NSObject *) cy$getProperty:(NSString *)name {
-    if ([name isEqualToString:@"length"]) {
-        NSUInteger count([self length]);
-#ifdef __APPLE__
-        return [NSNumber numberWithUnsignedInteger:count];
-#else
-        return [NSNumber numberWithUnsignedInt:count];
-#endif
-    }
-
     size_t index(CYGetIndex(name));
     if (index == _not(size_t) || index >= [self length])
         return [super cy$getProperty:name];
@@ -1082,12 +1145,7 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     }
 }
 
-// XXX: this might be overly restrictive for NSString; I think I need a half-way between /injecting/ implicit properties and /accepting/ implicit properties
-+ (bool) cy$hasImplicitProperties {
-    return false;
-}
-
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return CYCastJSValue(context, CYJSString(context, self));
 } CYObjectiveCatch }
 
@@ -1100,13 +1158,13 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
     return kJSTypeUndefined;
 }
 
-- (NSString *) cy$toCYON {
+- (NSString *) cy$toCYON:(bool)objective {
     NSString *value(@"undefined");
     return value; // XXX: maybe use the below code, adding @undefined?
     //return objective ? value : [NSString stringWithFormat:@"@%@", value];
 }
 
-- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_(context) {
+- (JSValueRef) cy$valueOfInContext:(JSContextRef)context { CYObjectiveTry_ {
     return CYJSUndefined(context);
 } CYObjectiveCatch }
 
@@ -1115,15 +1173,14 @@ NSObject *CYCopyNSObject(apr_pool_t *pool, JSContextRef context, JSValueRef valu
 
 static bool CYIsClass(id self) {
 #ifdef __APPLE__
-    // XXX: this is a lame object_isClass
-    return class_getInstanceMethod(object_getClass(self), @selector(alloc)) != NULL;
+    return class_isMetaClass(object_getClass(self));
 #else
     return GSObjCIsClass(self);
 #endif
 }
 
-Class CYCastClass(apr_pool_t *pool, JSContextRef context, JSValueRef value) {
-    id self(CYCastNSObject(pool, context, value));
+Class CYCastClass(CYPool &pool, JSContextRef context, JSValueRef value) {
+    id self(CYCastNSObject(&pool, context, value));
     if (CYIsClass(self))
         return (Class) self;
     throw CYJSError(context, "got something that is not a Class");
@@ -1135,7 +1192,7 @@ NSArray *CYCastNSArray(JSContextRef context, JSPropertyNameArrayRef names) {
     size_t size(JSPropertyNameArrayGetCount(names));
     NSMutableArray *array([NSMutableArray arrayWithCapacity:size]);
     for (size_t index(0); index != size; ++index)
-        [array addObject:CYCastNSString(pool, context, JSPropertyNameArrayGetNameAtIndex(names, index))];
+        [array addObject:CYCastNSString(&pool, context, JSPropertyNameArrayGetNameAtIndex(names, index))];
     return array;
 }
 
@@ -1148,7 +1205,7 @@ JSValueRef CYCastJSValue(JSContextRef context, NSObject *value) { CYPoolTry {
 
 @implementation CYJSObject
 
-- (id) initWithJSObject:(JSObjectRef)object inContext:(JSContextRef)context { CYObjectiveTry {
+- (id) initWithJSObject:(JSObjectRef)object inContext:(JSContextRef)context { CYObjectiveTry_ {
     if ((self = [super init]) != nil) {
         object_ = object;
         context_ = CYGetJSContext(context);
@@ -1165,9 +1222,7 @@ JSValueRef CYCastJSValue(JSContextRef context, NSObject *value) { CYPoolTry {
 
 - (NSString *) cy$toCYON:(bool)objective { CYObjectiveTry {
     CYPool pool;
-    JSValueRef exception(NULL);
-    const char *cyon(CYPoolCCYON(pool, context_, object_));
-    CYThrow(context_, exception);
+    const char *cyon(CYPoolCCYON(pool, context, object_));
     if (cyon == NULL)
         return [super cy$toCYON:objective];
     else
@@ -1175,46 +1230,44 @@ JSValueRef CYCastJSValue(JSContextRef context, NSObject *value) { CYPoolTry {
 } CYObjectiveCatch }
 
 - (NSUInteger) count { CYObjectiveTry {
-    JSPropertyNameArrayRef names(JSObjectCopyPropertyNames(context_, object_));
+    JSPropertyNameArrayRef names(JSObjectCopyPropertyNames(context, object_));
     size_t size(JSPropertyNameArrayGetCount(names));
     JSPropertyNameArrayRelease(names);
     return size;
 } CYObjectiveCatch }
 
 - (id) objectForKey:(id)key { CYObjectiveTry {
-    JSValueRef value(CYGetProperty(context_, object_, CYJSString(context_, (NSObject *) key)));
-    if (JSValueIsUndefined(context_, value))
+    JSValueRef value(CYGetProperty(context, object_, CYJSString(context, (NSObject *) key)));
+    if (JSValueIsUndefined(context, value))
         return nil;
-    return CYCastNSObject(NULL, context_, value) ?: [NSNull null];
+    return CYCastNSObject(NULL, context, value) ?: [NSNull null];
 } CYObjectiveCatch }
 
 - (NSEnumerator *) keyEnumerator { CYObjectiveTry {
-    JSPropertyNameArrayRef names(JSObjectCopyPropertyNames(context_, object_));
-    NSEnumerator *enumerator([CYCastNSArray(context_, names) objectEnumerator]);
+    JSPropertyNameArrayRef names(JSObjectCopyPropertyNames(context, object_));
+    NSEnumerator *enumerator([CYCastNSArray(context, names) objectEnumerator]);
     JSPropertyNameArrayRelease(names);
     return enumerator;
 } CYObjectiveCatch }
 
 - (void) setObject:(id)object forKey:(id)key { CYObjectiveTry {
-    CYSetProperty(context_, object_, CYJSString(context_, (NSObject *) key), CYCastJSValue(context_, (NSString *) object));
+    CYSetProperty(context, object_, CYJSString(context, (NSObject *) key), CYCastJSValue(context, (NSString *) object));
 } CYObjectiveCatch }
 
 - (void) removeObjectForKey:(id)key { CYObjectiveTry {
-    JSValueRef exception(NULL);
-    (void) JSObjectDeleteProperty(context_, object_, CYJSString(context_, (NSObject *) key), &exception);
-    CYThrow(context_, exception);
+    (void) _jsccall(JSObjectDeleteProperty, context, object_, CYJSString(context, (NSObject *) key));
 } CYObjectiveCatch }
 
 @end
 
 @implementation CYJSArray
 
-- (NSString *) cy$toCYON:(bool)objective {
+- (NSString *) cy$toCYON:(bool)objective { CYObjectiveTry {
     CYPool pool;
-    return [NSString stringWithUTF8String:CYPoolCCYON(pool, context_, object_)];
-}
+    return [NSString stringWithUTF8String:CYPoolCCYON(pool, context, object_)];
+} CYObjectiveCatch }
 
-- (id) initWithJSObject:(JSObjectRef)object inContext:(JSContextRef)context { CYObjectiveTry {
+- (id) initWithJSObject:(JSObjectRef)object inContext:(JSContextRef)context { CYObjectiveTry_ {
     if ((self = [super init]) != nil) {
         object_ = object;
         context_ = CYGetJSContext(context);
@@ -1230,62 +1283,54 @@ JSValueRef CYCastJSValue(JSContextRef context, NSObject *value) { CYPoolTry {
 } CYObjectiveCatch }
 
 - (NSUInteger) count { CYObjectiveTry {
-    return CYArrayLength(context_, object_);
+    return CYArrayLength(context, object_);
 } CYObjectiveCatch }
 
 - (id) objectAtIndex:(NSUInteger)index { CYObjectiveTry {
     size_t bounds([self count]);
     if (index >= bounds)
-        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray objectAtIndex:]: index (%zu) beyond bounds (%zu)", index, bounds] userInfo:nil];
-    JSValueRef exception(NULL);
-    JSValueRef value(JSObjectGetPropertyAtIndex(context_, object_, index, &exception));
-    CYThrow(context_, exception);
-    return CYCastNSObject(NULL, context_, value) ?: [NSNull null];
+        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray objectAtIndex:]: index (%zu) beyond bounds (%zu)", static_cast<size_t>(index), bounds] userInfo:nil];
+    JSValueRef value(_jsccall(JSObjectGetPropertyAtIndex, context, object_, index));
+    return CYCastNSObject(NULL, context, value) ?: [NSNull null];
 } CYObjectiveCatch }
 
 - (void) addObject:(id)object { CYObjectiveTry {
-    CYArrayPush(context_, object_, CYCastJSValue(context_, (NSObject *) object));
+    CYArrayPush(context, object_, CYCastJSValue(context, (NSObject *) object));
 } CYObjectiveCatch }
 
 - (void) insertObject:(id)object atIndex:(NSUInteger)index { CYObjectiveTry {
     size_t bounds([self count] + 1);
     if (index >= bounds)
-        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray insertObject:atIndex:]: index (%zu) beyond bounds (%zu)", index, bounds] userInfo:nil];
-    JSValueRef exception(NULL);
+        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray insertObject:atIndex:]: index (%zu) beyond bounds (%zu)", static_cast<size_t>(index), bounds] userInfo:nil];
     JSValueRef arguments[3];
-    arguments[0] = CYCastJSValue(context_, index);
-    arguments[1] = CYCastJSValue(context_, 0);
-    arguments[2] = CYCastJSValue(context_, (NSObject *) object);
-    JSObjectRef Array(CYGetCachedObject(context_, CYJSString("Array_prototype")));
-    JSObjectCallAsFunction(context_, CYCastJSObject(context_, CYGetProperty(context_, Array, splice_s)), object_, 3, arguments, &exception);
-    CYThrow(context_, exception);
+    arguments[0] = CYCastJSValue(context, index);
+    arguments[1] = CYCastJSValue(context, 0);
+    arguments[2] = CYCastJSValue(context, (NSObject *) object);
+    JSObjectRef Array(CYGetCachedObject(context, CYJSString("Array_prototype")));
+    _jsccall(JSObjectCallAsFunction, context, CYCastJSObject(context, CYGetProperty(context, Array, splice_s)), object_, 3, arguments);
 } CYObjectiveCatch }
 
 - (void) removeLastObject { CYObjectiveTry {
-    JSValueRef exception(NULL);
-    JSObjectRef Array(CYGetCachedObject(context_, CYJSString("Array_prototype")));
-    JSObjectCallAsFunction(context_, CYCastJSObject(context_, CYGetProperty(context_, Array, pop_s)), object_, 0, NULL, &exception);
-    CYThrow(context_, exception);
+    JSObjectRef Array(CYGetCachedObject(context, CYJSString("Array_prototype")));
+    _jsccall(JSObjectCallAsFunction, context, CYCastJSObject(context, CYGetProperty(context, Array, pop_s)), object_, 0, NULL);
 } CYObjectiveCatch }
 
 - (void) removeObjectAtIndex:(NSUInteger)index { CYObjectiveTry {
     size_t bounds([self count]);
     if (index >= bounds)
-        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray removeObjectAtIndex:]: index (%zu) beyond bounds (%zu)", index, bounds] userInfo:nil];
-    JSValueRef exception(NULL);
+        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray removeObjectAtIndex:]: index (%zu) beyond bounds (%zu)", static_cast<size_t>(index), bounds] userInfo:nil];
     JSValueRef arguments[2];
-    arguments[0] = CYCastJSValue(context_, index);
-    arguments[1] = CYCastJSValue(context_, 1);
-    JSObjectRef Array(CYGetCachedObject(context_, CYJSString("Array_prototype")));
-    JSObjectCallAsFunction(context_, CYCastJSObject(context_, CYGetProperty(context_, Array, splice_s)), object_, 2, arguments, &exception);
-    CYThrow(context_, exception);
+    arguments[0] = CYCastJSValue(context, index);
+    arguments[1] = CYCastJSValue(context, 1);
+    JSObjectRef Array(CYGetCachedObject(context, CYJSString("Array_prototype")));
+    _jsccall(JSObjectCallAsFunction, context, CYCastJSObject(context, CYGetProperty(context, Array, splice_s)), object_, 2, arguments);
 } CYObjectiveCatch }
 
 - (void) replaceObjectAtIndex:(NSUInteger)index withObject:(id)object { CYObjectiveTry {
     size_t bounds([self count]);
     if (index >= bounds)
-        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray replaceObjectAtIndex:withObject:]: index (%zu) beyond bounds (%zu)", index, bounds] userInfo:nil];
-    CYSetProperty(context_, object_, index, CYCastJSValue(context_, (NSObject *) object));
+        @throw [NSException exceptionWithName:NSRangeException reason:[NSString stringWithFormat:@"*** -[CYJSArray replaceObjectAtIndex:withObject:]: index (%zu) beyond bounds (%zu)", static_cast<size_t>(index), bounds] userInfo:nil];
+    CYSetProperty(context, object_, index, CYCastJSValue(context, (NSObject *) object));
 } CYObjectiveCatch }
 
 @end
@@ -1300,18 +1345,18 @@ JSValueRef CYCastJSValue(JSContextRef context, NSObject *value) { CYPoolTry {
 
 @implementation CYInternal
 
-- (void) dealloc {
+- (void) dealloc { CYObjectiveTry {
     JSValueUnprotect(context_, object_);
     JSGlobalContextRelease(context_);
     [super dealloc];
-}
+} CYObjectiveCatch }
 
-- (id) initInContext:(JSContextRef)context {
+- (id) initInContext:(JSContextRef)context { CYObjectiveTry_ {
     if ((self = [super init]) != nil) {
         context_ = CYGetJSContext(context);
         JSGlobalContextRetain(context_);
     } return self;
-}
+} CYObjectiveCatch }
 
 - (bool) hasProperty:(JSStringRef)name inContext:(JSContextRef)context {
     if (object_ == NULL)
@@ -1406,12 +1451,13 @@ static void CYObjectiveC_CallFunction(JSContextRef context, ffi_cif *cif, void (
     ffi_call(cif, function, value, values);
 } CYSadCatch() }
 
-static bool CYObjectiveC_PoolFFI(apr_pool_t *pool, JSContextRef context, sig::Type *type, ffi_type *ffi, void *data, JSValueRef value) { CYSadTry {
+static bool CYObjectiveC_PoolFFI(CYPool *pool, JSContextRef context, sig::Type *type, ffi_type *ffi, void *data, JSValueRef value) { CYSadTry {
     switch (type->primitive) {
         // XXX: do something epic about blocks
         case sig::block_P:
         case sig::object_P:
         case sig::typename_P:
+            // XXX: this works for return values, but not for properties and fields
             *reinterpret_cast<id *>(data) = CYCastNSObject(pool, context, value);
         break;
 
@@ -1471,7 +1517,7 @@ static bool CYImplements(id object, Class _class, SEL selector, bool devoid = fa
     return false;
 }
 
-static const char *CYPoolTypeEncoding(apr_pool_t *pool, JSContextRef context, SEL sel, objc_method *method) {
+static const char *CYPoolTypeEncoding(CYPool &pool, JSContextRef context, SEL sel, objc_method *method) {
     if (method != NULL)
         return method_getTypeEncoding(method);
 
@@ -1489,21 +1535,13 @@ static const char *CYPoolTypeEncoding(apr_pool_t *pool, JSContextRef context, SE
     return NULL;
 }
 
-static void MessageClosure_(ffi_cif *cif, void *result, void **arguments, void *arg) {
-    Closure_privateData *internal(reinterpret_cast<Closure_privateData *>(arg));
-
-    JSContextRef context(internal->context_);
-
-    size_t count(internal->cif_.nargs);
-    JSValueRef values[count];
-
-    for (size_t index(0); index != count; ++index)
-        values[index] = CYFromFFI(context, internal->signature_.elements[1 + index].type, internal->cif_.arg_types[index], arguments[index]);
-
+static JSValueRef MessageAdapter_(JSContextRef context, size_t count, JSValueRef values[], JSObjectRef function) {
     JSObjectRef _this(CYCastJSObject(context, values[0]));
+    return CYCallAsFunction(context, function, _this, count - 2, values + 2);
+}
 
-    JSValueRef value(CYCallAsFunction(context, internal->function_, _this, count - 2, values + 2));
-    CYPoolFFI(NULL, context, internal->signature_.elements[0].type, internal->cif_.rtype, result, value);
+static void MessageClosure_(ffi_cif *cif, void *result, void **arguments, void *arg) {
+    CYExecuteClosure(cif, result, arguments, arg, &MessageAdapter_);
 }
 
 static JSObjectRef CYMakeMessage(JSContextRef context, SEL sel, IMP imp, const char *type) {
@@ -1511,9 +1549,12 @@ static JSObjectRef CYMakeMessage(JSContextRef context, SEL sel, IMP imp, const c
     return JSObjectMake(context, Message_, internal);
 }
 
-static IMP CYMakeMessage(JSContextRef context, JSValueRef value, const char *type) {
+static IMP CYMakeMessage(JSContextRef context, JSValueRef value, const char *encoding) {
     JSObjectRef function(CYCastJSObject(context, value));
-    Closure_privateData *internal(CYMakeFunctor_(context, function, type, &MessageClosure_));
+    CYPool pool;
+    sig::Signature signature;
+    sig::Parse(pool, &signature, encoding, &Structor_);
+    Closure_privateData *internal(CYMakeFunctor_(context, function, signature, &MessageClosure_));
     // XXX: see notes in Library.cpp about needing to leak
     return reinterpret_cast<IMP>(internal->GetValue());
 }
@@ -1532,7 +1573,7 @@ static bool Messages_hasProperty(JSContextRef context, JSObjectRef object, JSStr
     return false;
 }
 
-static JSValueRef Messages_getProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) {
+static JSValueRef Messages_getProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Messages *internal(reinterpret_cast<Messages *>(JSObjectGetPrivate(object)));
     Class _class(internal->GetValue());
 
@@ -1544,9 +1585,9 @@ static JSValueRef Messages_getProperty(JSContextRef context, JSObjectRef object,
             return CYMakeMessage(context, sel, method_getImplementation(method), method_getTypeEncoding(method));
 
     return NULL;
-}
+} CYCatch(NULL) }
 
-static bool Messages_setProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef value, JSValueRef *exception) {
+static bool Messages_setProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef value, JSValueRef *exception) { CYTry {
     Messages *internal(reinterpret_cast<Messages *>(JSObjectGetPrivate(object)));
     Class _class(internal->GetValue());
 
@@ -1583,10 +1624,10 @@ static bool Messages_setProperty(JSContextRef context, JSObjectRef object, JSStr
     }
 
     return true;
-}
+} CYCatch(false) }
 
 #if 0 && OBJC_API_VERSION < 2
-static bool Messages_deleteProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) {
+static bool Messages_deleteProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Messages *internal(reinterpret_cast<Messages *>(JSObjectGetPrivate(object)));
     Class _class(internal->GetValue());
 
@@ -1601,7 +1642,7 @@ static bool Messages_deleteProperty(JSContextRef context, JSObjectRef object, JS
         }
 
     return false;
-}
+} CYCatch(false) }
 #endif
 
 static void Messages_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
@@ -1636,7 +1677,7 @@ static bool Instance_hasProperty(JSContextRef context, JSObjectRef object, JSStr
         return true;
 
     CYPool pool;
-    NSString *name(CYCastNSString(pool, context, property));
+    NSString *name(CYCastNSString(&pool, context, property));
 
     if (CYInternal *internal = [CYInternal get:self])
         if ([internal hasProperty:property inContext:context])
@@ -1674,15 +1715,15 @@ static JSValueRef Instance_getProperty(JSContextRef context, JSObjectRef object,
         return Internal::Make(context, self, object);
 
     CYPool pool;
-    NSString *name(CYCastNSString(pool, context, property));
+    NSString *name(CYCastNSString(&pool, context, property));
 
     if (CYInternal *internal = [CYInternal get:self])
         if (JSValueRef value = [internal getProperty:property inContext:context])
             return value;
 
     CYPoolTry {
-        if (NSObject *data = [self cy$getProperty:name])
-            return CYCastJSValue(context, data);
+        if (JSValueRef value = [self cy$getProperty:name inContext:context])
+            return value;
     } CYPoolCatch(NULL)
 
     const char *string(CYPoolCString(pool, context, name));
@@ -1692,17 +1733,17 @@ static JSValueRef Instance_getProperty(JSContextRef context, JSObjectRef object,
     if (objc_property_t property = class_getProperty(_class, string)) {
         PropertyAttributes attributes(property);
         SEL sel(sel_registerName(attributes.Getter()));
-        return CYSendMessage(pool, context, self, NULL, sel, 0, NULL, false, exception);
+        return CYSendMessage(pool, context, self, NULL, sel, 0, NULL, false);
     }
 #endif
 
     if (CYHasImplicitProperties(_class))
         if (SEL sel = sel_getUid(string))
             if (CYImplements(self, _class, sel, true))
-                return CYSendMessage(pool, context, self, NULL, sel, 0, NULL, false, exception);
+                return CYSendMessage(pool, context, self, NULL, sel, 0, NULL, false);
 
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
 static bool Instance_setProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef value, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
@@ -1710,13 +1751,13 @@ static bool Instance_setProperty(JSContextRef context, JSObjectRef object, JSStr
 
     CYPool pool;
 
-    NSString *name(CYCastNSString(pool, context, property));
-    NSObject *data(CYCastNSObject(pool, context, value));
+    NSString *name(CYCastNSString(&pool, context, property));
+    NSObject *data(CYCastNSObject(&pool, context, value));
 
     CYPoolTry {
         if ([self cy$setProperty:name to:data])
             return true;
-    } CYPoolCatch(NULL)
+    } CYPoolCatch(false)
 
     const char *string(CYPoolCString(pool, context, name));
     Class _class(object_getClass(self));
@@ -1727,7 +1768,7 @@ static bool Instance_setProperty(JSContextRef context, JSObjectRef object, JSStr
         if (const char *setter = attributes.Setter()) {
             SEL sel(sel_registerName(setter));
             JSValueRef arguments[1] = {value};
-            CYSendMessage(pool, context, self, NULL, sel, 1, arguments, false, exception);
+            CYSendMessage(pool, context, self, NULL, sel, 1, arguments, false);
             return true;
         }
     }
@@ -1752,7 +1793,7 @@ static bool Instance_setProperty(JSContextRef context, JSObjectRef object, JSStr
     if (SEL sel = sel_getUid(set))
         if (CYImplements(self, _class, sel)) {
             JSValueRef arguments[1] = {value};
-            CYSendMessage(pool, context, self, NULL, sel, 1, arguments, false, exception);
+            CYSendMessage(pool, context, self, NULL, sel, 1, arguments, false);
             return true;
         }
 
@@ -1762,7 +1803,7 @@ static bool Instance_setProperty(JSContextRef context, JSObjectRef object, JSStr
     }
 
     return false;
-} CYCatch }
+} CYCatch(false) }
 
 static bool Instance_deleteProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
@@ -1771,8 +1812,8 @@ static bool Instance_deleteProperty(JSContextRef context, JSObjectRef object, JS
     CYPoolTry {
         NSString *name(CYCastNSString(NULL, context, property));
         return [self cy$deleteProperty:name];
-    } CYPoolCatch(NULL)
-} CYCatch return /*XXX*/ NULL; }
+    } CYPoolCatch(false)
+} CYCatch(false) return /*XXX*/ false; }
 
 static void Instance_getPropertyNames_message(JSPropertyNameAccumulatorRef names, objc_method *method) {
     const char *name(sel_getName(method_getName(method)));
@@ -1829,7 +1870,7 @@ static JSObjectRef Instance_callAsConstructor(JSContextRef context, JSObjectRef
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
     JSObjectRef value(Instance::Make(context, [internal->GetValue() alloc], Instance::Uninitialized));
     return value;
-} CYCatch }
+} CYCatch(NULL) }
 
 static JSValueRef Instance_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
@@ -1843,40 +1884,7 @@ static JSValueRef Instance_callAsFunction(JSContextRef context, JSObjectRef obje
     // to do /that/, generalize the various "is exactly Instance_" checks
     // then, move Instance_callAsFunction to only be on FunctionInstance
 
-    struct BlockDescriptor1 {
-        unsigned long int reserved;
-        unsigned long int size;
-    };
-
-    struct BlockDescriptor2 {
-        void (*copy_helper)(void *dst, void *src);
-        void (*dispose_helper)(void *src);
-    };
-
-    struct BlockDescriptor3 {
-        const char *signature;
-        const char *layout;
-    };
-
-    struct BlockLiteral {
-        Class isa;
-        int flags;
-        int reserved;
-        void (*invoke)(void *, ...);
-        void *descriptor;
-    } *literal = reinterpret_cast<BlockLiteral *>(self);
-
-    enum {
-        BLOCK_DEALLOCATING = 0x0001,
-        BLOCK_REFCOUNT_MASK = 0xfffe,
-        BLOCK_NEEDS_FREE = 1 << 24,
-        BLOCK_HAS_COPY_DISPOSE = 1 << 25,
-        BLOCK_HAS_CTOR = 1 << 26,
-        BLOCK_IS_GC = 1 << 27,
-        BLOCK_IS_GLOBAL = 1 << 28,
-        BLOCK_HAS_STRET = 1 << 29,
-        BLOCK_HAS_SIGNATURE = 1 << 30,
-    };
+    BlockLiteral *literal(reinterpret_cast<BlockLiteral *>(self));
 
     if ((literal->flags & BLOCK_HAS_SIGNATURE) != 0) {
         uint8_t *descriptor(reinterpret_cast<uint8_t *>(literal->descriptor));
@@ -1898,7 +1906,7 @@ static JSValueRef Instance_callAsFunction(JSContextRef context, JSObjectRef obje
             sig::sig_ffi_cif(pool, &sig::ObjectiveC, &signature, &cif);
 
             void (*function)() = reinterpret_cast<void (*)()>(literal->invoke);
-            return CYCallFunction(pool, context, 1, setup, count, arguments, false, exception, &signature, &cif, function);
+            return CYCallFunction(pool, context, 1, setup, count, arguments, false, &signature, &cif, function);
         }
     }
 
@@ -1910,7 +1918,7 @@ static JSValueRef Instance_callAsFunction(JSContextRef context, JSObjectRef obje
     } CYPoolCatch(NULL);
 
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
 static bool Instance_hasInstance(JSContextRef context, JSObjectRef constructor, JSValueRef instance, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate((JSObjectRef) constructor)));
@@ -1918,24 +1926,24 @@ static bool Instance_hasInstance(JSContextRef context, JSObjectRef constructor,
     if (!CYIsClass(_class))
         return false;
 
-    if (JSValueIsObjectOfClass(context, instance, Instance_)) {
+    if (CYJSValueIsNSObject(context, instance)) {
         Instance *linternal(reinterpret_cast<Instance *>(JSObjectGetPrivate((JSObjectRef) instance)));
         // XXX: this isn't always safe
         return [linternal->GetValue() isKindOfClass:_class];
     }
 
     return false;
-} CYCatch }
+} CYCatch(false) }
 
 static JSValueRef Instance_box_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     if (count == 0)
         throw CYJSError(context, "incorrect number of arguments to Instance");
     CYPool pool;
-    id value(CYCastNSObject(pool, context, arguments[0]));
+    id value(CYCastNSObject(&pool, context, arguments[0]));
     if (value == nil)
         value = [NSNull null];
     return CYCastJSValue(context, [value cy$box]);
-} CYCatch }
+} CYCatch(NULL) }
 
 static bool Internal_hasProperty(JSContextRef context, JSObjectRef object, JSStringRef property) {
     Internal *internal(reinterpret_cast<Internal *>(JSObjectGetPrivate(object)));
@@ -1950,6 +1958,23 @@ static bool Internal_hasProperty(JSContextRef context, JSObjectRef object, JSStr
     return false;
 }
 
+static void CYBitField(unsigned &length, unsigned &shift, id self, Ivar ivar, const char *encoding, unsigned offset) {
+    length = CYCastDouble(encoding + 1);
+    shift = 0;
+
+    unsigned int size;
+    objc_ivar **ivars(class_copyIvarList(object_getClass(self), &size));
+    for (size_t i(0); i != size; ++i)
+        if (ivars[i] == ivar)
+            break;
+        else if (ivar_getOffset(ivars[i]) == offset) {
+            const char *encoding(ivar_getTypeEncoding(ivars[i]));
+            _assert(encoding[0] == 'b');
+            shift += CYCastDouble(encoding + 1);
+        }
+    free(ivars);
+}
+
 static JSValueRef Internal_getProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Internal *internal(reinterpret_cast<Internal *>(JSObjectGetPrivate(object)));
     CYPool pool;
@@ -1957,14 +1982,31 @@ static JSValueRef Internal_getProperty(JSContextRef context, JSObjectRef object,
     id self(internal->GetValue());
     const char *name(CYPoolCString(pool, context, property));
 
+#ifdef __arm64__
+    if (strcmp(name, "isa") == 0)
+        return CYCastJSValue(context, object_getClass(self));
+#endif
+
     if (objc_ivar *ivar = object_getInstanceVariable(self, name, NULL)) {
-        Type_privateData type(pool, ivar_getTypeEncoding(ivar));
-        // XXX: if this fails and throws an exception the person we are throwing it to gets the wrong exception
-        return CYFromFFI(context, type.type_, type.GetFFI(), reinterpret_cast<uint8_t *>(self) + ivar_getOffset(ivar));
+        ptrdiff_t offset(ivar_getOffset(ivar));
+        void *data(reinterpret_cast<uint8_t *>(self) + offset);
+
+        const char *encoding(ivar_getTypeEncoding(ivar));
+        if (encoding[0] == 'b') {
+            unsigned length, shift;
+            CYBitField(length, shift, self, ivar, encoding, offset);
+            _assert(shift + length <= sizeof(uintptr_t) * 8);
+            uintptr_t &field(*reinterpret_cast<uintptr_t *>(data));
+            uintptr_t mask((1 << length) - 1);
+            return CYCastJSValue(context, (field >> shift) & mask);
+        } else {
+            Type_privateData type(pool, ivar_getTypeEncoding(ivar));
+            return CYFromFFI(context, type.type_, type.GetFFI(), data);
+        }
     }
 
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
 static bool Internal_setProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef value, JSValueRef *exception) { CYTry {
     Internal *internal(reinterpret_cast<Internal *>(JSObjectGetPrivate(object)));
@@ -1974,13 +2016,26 @@ static bool Internal_setProperty(JSContextRef context, JSObjectRef object, JSStr
     const char *name(CYPoolCString(pool, context, property));
 
     if (objc_ivar *ivar = object_getInstanceVariable(self, name, NULL)) {
-        Type_privateData type(pool, ivar_getTypeEncoding(ivar));
-        CYPoolFFI(pool, context, type.type_, type.GetFFI(), reinterpret_cast<uint8_t *>(self) + ivar_getOffset(ivar), value);
-        return true;
+        ptrdiff_t offset(ivar_getOffset(ivar));
+        void *data(reinterpret_cast<uint8_t *>(self) + offset);
+
+        const char *encoding(ivar_getTypeEncoding(ivar));
+        if (encoding[0] == 'b') {
+            unsigned length, shift;
+            CYBitField(length, shift, self, ivar, encoding, offset);
+            _assert(shift + length <= sizeof(uintptr_t) * 8);
+            uintptr_t &field(*reinterpret_cast<uintptr_t *>(data));
+            uintptr_t mask((1 << length) - 1);
+            field = field & ~(mask << shift) | (uintptr_t(CYCastDouble(context, value)) & mask) << shift;
+        } else {
+            Type_privateData type(pool, ivar_getTypeEncoding(ivar));
+            CYPoolFFI(&pool, context, type.type_, type.GetFFI(), reinterpret_cast<uint8_t *>(self) + ivar_getOffset(ivar), value);
+            return true;
+        }
     }
 
     return false;
-} CYCatch }
+} CYCatch(false) }
 
 static void Internal_getPropertyNames_(Class _class, JSPropertyNameAccumulatorRef names) {
     if (Class super = class_getSuperclass(_class))
@@ -2009,39 +2064,51 @@ static void Internal_getPropertyNames(JSContextRef context, JSObjectRef object,
     Internal_getPropertyNames_(_class, names);
 }
 
-static JSValueRef Internal_callAsFunction_$cya(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) {
+static JSValueRef Internal_callAsFunction_$cya(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     Internal *internal(reinterpret_cast<Internal *>(JSObjectGetPrivate(object)));
     return internal->GetOwner();
-}
+} CYCatch(NULL) }
 
 static JSValueRef ObjectiveC_Classes_getProperty(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     CYPool pool;
-    NSString *name(CYCastNSString(pool, context, property));
+    NSString *name(CYCastNSString(&pool, context, property));
     if (Class _class = NSClassFromString(name))
         return CYMakeInstance(context, _class, true);
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
-static void ObjectiveC_Classes_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
 #ifdef __APPLE__
-    size_t size(objc_getClassList(NULL, 0));
+static Class *CYCopyClassList(size_t &size) {
+    size = objc_getClassList(NULL, 0);
     Class *data(reinterpret_cast<Class *>(malloc(sizeof(Class) * size)));
 
-  get:
-    size_t writ(objc_getClassList(data, size));
-    if (size < writ) {
+    for (;;) {
+        size_t writ(objc_getClassList(data, size));
+        if (writ <= size) {
+            size = writ;
+            return data;
+        }
+
+        Class *copy(reinterpret_cast<Class *>(realloc(data, sizeof(Class) * writ)));
+        if (copy == NULL) {
+            free(data);
+            return NULL;
+        }
+
+        data = copy;
         size = writ;
-        if (Class *copy = reinterpret_cast<Class *>(realloc(data, sizeof(Class) * writ))) {
-            data = copy;
-            goto get;
-        } else goto done;
     }
+}
+#endif
 
-    for (size_t i(0); i != writ; ++i)
-        JSPropertyNameAccumulatorAddName(names, CYJSString(class_getName(data[i])));
-
-  done:
-    free(data);
+static void ObjectiveC_Classes_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
+#ifdef __APPLE__
+    size_t size;
+    if (Class *data = CYCopyClassList(size)) {
+        for (size_t i(0); i != size; ++i)
+            JSPropertyNameAccumulatorAddName(names, CYJSString(class_getName(data[i])));
+        free(data);
+    }
 #else
     void *state(NULL);
     while (Class _class = objc_next_class(&state))
@@ -2070,7 +2137,7 @@ static JSValueRef ObjectiveC_Image_Classes_getProperty(JSContextRef context, JSO
   free:
     free(data);
     return value;
-} CYCatch }
+} CYCatch(NULL) }
 
 static void ObjectiveC_Image_Classes_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
     const char *internal(reinterpret_cast<const char *>(JSObjectGetPrivate(object)));
@@ -2099,7 +2166,7 @@ static JSValueRef ObjectiveC_Images_getProperty(JSContextRef context, JSObjectRe
     JSObjectRef value(JSObjectMake(context, NULL, NULL));
     CYSetProperty(context, value, CYJSString("classes"), JSObjectMake(context, ObjectiveC_Image_Classes_, const_cast<char *>(name)));
     return value;
-} CYCatch }
+} CYCatch(NULL) }
 
 static void ObjectiveC_Images_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
     unsigned int size;
@@ -2116,7 +2183,7 @@ static JSValueRef ObjectiveC_Protocols_getProperty(JSContextRef context, JSObjec
     if (Protocol *protocol = objc_getProtocol(name))
         return CYMakeInstance(context, protocol, true);
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
 static void ObjectiveC_Protocols_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
 #if OBJC_API_VERSION >= 2
@@ -2136,13 +2203,118 @@ static JSValueRef ObjectiveC_Constants_getProperty(JSContextRef context, JSObjec
     if (name == "nil")
         return Instance::Make(context, nil);
     return NULL;
-} CYCatch }
+} CYCatch(NULL) }
 
 static void ObjectiveC_Constants_getPropertyNames(JSContextRef context, JSObjectRef object, JSPropertyNameAccumulatorRef names) {
     JSPropertyNameAccumulatorAddName(names, CYJSString("nil"));
 }
 
 #ifdef __APPLE__
+static kern_return_t CYReadMemory(task_t task, vm_address_t address, vm_size_t size, void **data) {
+    *data = reinterpret_cast<void *>(address);
+    return KERN_SUCCESS;
+}
+
+struct CYChoice {
+    std::set<Class> query_;
+    JSContextRef context_;
+    JSObjectRef results_;
+};
+
+struct CYObjectStruct {
+    Class isa_;
+};
+
+static void choose_(task_t task, void *baton, unsigned type, vm_range_t *ranges, unsigned count) {
+    CYChoice *choice(reinterpret_cast<CYChoice *>(baton));
+    JSContextRef context(choice->context_);
+
+    for (unsigned i(0); i != count; ++i) {
+        vm_range_t &range(ranges[i]);
+        void *data(reinterpret_cast<void *>(range.address));
+        size_t size(range.size);
+
+        if (size < sizeof(CYObjectStruct))
+            continue;
+
+        uintptr_t *pointers(reinterpret_cast<uintptr_t *>(data));
+#ifdef __arm64__
+        Class isa(reinterpret_cast<Class>(pointers[0] & 0x1fffffff8));
+#else
+        Class isa(reinterpret_cast<Class>(pointers[0]));
+#endif
+
+        std::set<Class>::const_iterator result(choice->query_.find(isa));
+        if (result == choice->query_.end())
+            continue;
+
+        // XXX: if (size < class_getInstanceSize(*result))
+        if ((class_getInstanceSize(*result) + 15) / 16 * 16 != size)
+            continue;
+        CYArrayPush(context, choice->results_, CYCastJSValue(context, reinterpret_cast<id>(data)));
+    }
+}
+
+static JSValueRef choose(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
+    if (count != 1)
+        throw CYJSError(context, "choose() takes a class argument");
+
+    CYPool pool;
+    Class _class(CYCastNSObject(&pool, context, arguments[0]));
+
+    vm_address_t *zones(NULL);
+    unsigned size(0);
+    kern_return_t error(malloc_get_all_zones(0, &CYReadMemory, &zones, &size));
+    _assert(error == KERN_SUCCESS);
+
+    JSObjectRef Array(CYGetCachedObject(context, CYJSString("Array")));
+    JSObjectRef results(_jsccall(JSObjectCallAsConstructor, context, Array, 0, NULL));
+
+    CYChoice choice;
+    choice.context_ = context;
+    choice.results_ = results;
+
+    size_t number;
+    Class *classes(CYCopyClassList(number));
+    _assert(classes != NULL);
+
+    for (size_t i(0); i != number; ++i)
+        for (Class current(classes[i]); current != Nil; current = class_getSuperclass(current))
+            if (current == _class) {
+                choice.query_.insert(classes[i]);
+                break;
+            }
+
+    free(classes);
+
+    for (unsigned i(0); i != size; ++i) {
+        const malloc_zone_t *zone(reinterpret_cast<const malloc_zone_t *>(zones[i]));
+        if (zone == NULL || zone->introspect == NULL)
+            continue;
+
+        zone->introspect->enumerator(mach_task_self(), &choice, MALLOC_PTR_IN_USE_RANGE_TYPE, zones[i], &CYReadMemory, &choose_);
+    }
+
+    return results;
+} CYCatch(NULL) }
+#endif
+
+#ifdef __APPLE__
+#if defined(__i386__) || defined(__x86_64__)
+#define OBJC_MAX_STRUCT_BY_VALUE 8
+static int struct_forward_array[] = {
+    0, 0, 0, 1, 0, 1, 1, 1, 0 };
+#elif defined(__arm__)
+#define OBJC_MAX_STRUCT_BY_VALUE 1
+static int struct_forward_array[] = {
+    0, 0 };
+#elif defined(__arm64__)
+#define CY_NO_STRET
+#else
+#error missing objc-runtime-info
+#endif
+
+#ifndef CY_NO_STRET
 static bool stret(ffi_type *ffi_type) {
     return ffi_type->type == FFI_TYPE_STRUCT && (
         ffi_type->size > OBJC_MAX_STRUCT_BY_VALUE ||
@@ -2150,8 +2322,9 @@ static bool stret(ffi_type *ffi_type) {
     );
 }
 #endif
+#endif
 
-JSValueRef CYSendMessage(apr_pool_t *pool, JSContextRef context, id self, Class _class, SEL _cmd, size_t count, const JSValueRef arguments[], bool initialize, JSValueRef *exception) { CYTry {
+JSValueRef CYSendMessage(CYPool &pool, JSContextRef context, id self, Class _class, SEL _cmd, size_t count, const JSValueRef arguments[], bool initialize) {
     const char *type;
 
     if (_class == NULL)
@@ -2205,9 +2378,11 @@ JSValueRef CYSendMessage(apr_pool_t *pool, JSContextRef context, id self, Class
 
     if (imp == NULL) {
 #ifdef __APPLE__
+#ifndef CY_NO_STRET
         if (stret(cif.rtype))
             imp = class_getMethodImplementation_stret(_class, _cmd);
         else
+#endif
             imp = class_getMethodImplementation(_class, _cmd);
 #else
         objc_super super = {self, _class};
@@ -2216,10 +2391,10 @@ JSValueRef CYSendMessage(apr_pool_t *pool, JSContextRef context, id self, Class
     }
 
     void (*function)() = reinterpret_cast<void (*)()>(imp);
-    return CYCallFunction(pool, context, 2, setup, count, arguments, initialize, exception, &signature, &cif, function);
-} CYCatch }
+    return CYCallFunction(pool, context, 2, setup, count, arguments, initialize, &signature, &cif, function);
+}
 
-static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
+static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[]) {
     if (count < 2)
         throw CYJSError(context, "too few arguments to objc_msgSend");
 
@@ -2236,7 +2411,7 @@ static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObje
         self = internal->GetValue();
         _class = internal->class_;;
         uninitialized = false;
-    } else if (JSValueIsObjectOfClass(context, arguments[0], Instance_)) {
+    } else if (CYJSValueIsNSObject(context, arguments[0])) {
         Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate((JSObjectRef) arguments[0])));
         self = internal->GetValue();
         _class = nil;
@@ -2244,7 +2419,7 @@ static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObje
         if (uninitialized)
             internal->value_ = nil;
     } else {
-        self = CYCastNSObject(pool, context, arguments[0]);
+        self = CYCastNSObject(&pool, context, arguments[0]);
         _class = nil;
         uninitialized = false;
     }
@@ -2254,39 +2429,43 @@ static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObje
 
     _cmd = CYCastSEL(context, arguments[1]);
 
-    return CYSendMessage(pool, context, self, _class, _cmd, count - 2, arguments + 2, uninitialized, exception);
-} CYCatch }
+    return CYSendMessage(pool, context, self, _class, _cmd, count - 2, arguments + 2, uninitialized);
+}
 
-static JSValueRef Selector_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) {
+static JSValueRef $objc_msgSend(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
+    return $objc_msgSend(context, object, _this, count, arguments);
+} CYCatch(NULL) }
+
+static JSValueRef Selector_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     JSValueRef setup[count + 2];
     setup[0] = _this;
     setup[1] = object;
     memcpy(setup + 2, arguments, sizeof(JSValueRef) * count);
-    return $objc_msgSend(context, NULL, NULL, count + 2, setup, exception);
-}
+    return $objc_msgSend(context, NULL, NULL, count + 2, setup);
+} CYCatch(NULL) }
 
-static JSValueRef Message_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) {
+static JSValueRef Message_callAsFunction(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     CYPool pool;
     Message_privateData *internal(reinterpret_cast<Message_privateData *>(JSObjectGetPrivate(object)));
 
     // XXX: handle Instance::Uninitialized?
-    id self(CYCastNSObject(pool, context, _this));
+    id self(CYCastNSObject(&pool, context, _this));
 
     void *setup[2];
     setup[0] = &self;
     setup[1] = &internal->sel_;
 
-    return CYCallFunction(pool, context, 2, setup, count, arguments, false, exception, &internal->signature_, &internal->cif_, internal->GetValue());
-}
+    return CYCallFunction(pool, context, 2, setup, count, arguments, false, &internal->signature_, &internal->cif_, internal->GetValue());
+} CYCatch(NULL) }
 
 static JSObjectRef Super_new(JSContextRef context, JSObjectRef object, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     if (count != 2)
         throw CYJSError(context, "incorrect number of arguments to Super constructor");
     CYPool pool;
-    id self(CYCastNSObject(pool, context, arguments[0]));
+    id self(CYCastNSObject(&pool, context, arguments[0]));
     Class _class(CYCastClass(pool, context, arguments[1]));
     return cy::Super::Make(context, self, _class);
-} CYCatch }
+} CYCatch(NULL) }
 
 static JSObjectRef Selector_new(JSContextRef context, JSObjectRef object, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     if (count != 1)
@@ -2294,21 +2473,21 @@ static JSObjectRef Selector_new(JSContextRef context, JSObjectRef object, size_t
     CYPool pool;
     const char *name(CYPoolCString(pool, context, arguments[0]));
     return CYMakeSelector(context, sel_registerName(name));
-} CYCatch }
+} CYCatch(NULL) }
 
 static JSObjectRef Instance_new(JSContextRef context, JSObjectRef object, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     if (count > 1)
         throw CYJSError(context, "incorrect number of arguments to Instance constructor");
     id self(count == 0 ? nil : CYCastPointer<id>(context, arguments[0]));
     return CYMakeInstance(context, self, false);
-} CYCatch }
+} CYCatch(NULL) }
 
-static JSValueRef CYValue_getProperty_value(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) {
+static JSValueRef CYValue_getProperty_value(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     CYValue *internal(reinterpret_cast<CYValue *>(JSObjectGetPrivate(object)));
     return CYCastJSValue(context, reinterpret_cast<uintptr_t>(internal->value_));
-}
+} CYCatch(NULL) }
 
-static JSValueRef CYValue_callAsFunction_$cya(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) {
+static JSValueRef CYValue_callAsFunction_$cya(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     CYValue *internal(reinterpret_cast<CYValue *>(JSObjectGetPrivate(_this)));
     Type_privateData *typical(internal->GetType());
 
@@ -2324,12 +2503,12 @@ static JSValueRef CYValue_callAsFunction_$cya(JSContextRef context, JSObjectRef
     }
 
     return CYMakePointer(context, &internal->value_, _not(size_t), type, ffi, object);
-}
+} CYCatch(NULL) }
 
-static JSValueRef Instance_getProperty_constructor(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) {
+static JSValueRef Instance_getProperty_constructor(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
     return Instance::Make(context, (id) object_getClass(internal->GetValue()));
-}
+} CYCatch(NULL) }
 
 static JSValueRef Instance_getProperty_prototype(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
@@ -2337,26 +2516,26 @@ static JSValueRef Instance_getProperty_prototype(JSContextRef context, JSObjectR
     if (!CYIsClass(self))
         return CYJSUndefined(context);
     return CYGetClassPrototype(context, self);
-} CYCatch }
+} CYCatch(NULL) }
 
-static JSValueRef Instance_getProperty_messages(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) {
+static JSValueRef Instance_getProperty_messages(JSContextRef context, JSObjectRef object, JSStringRef property, JSValueRef *exception) { CYTry {
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(object)));
     id self(internal->GetValue());
     if (!CYIsClass(self))
         return CYJSUndefined(context);
     return Messages::Make(context, (Class) self);
-}
+} CYCatch(NULL) }
 
 static JSValueRef Instance_callAsFunction_toCYON(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
-    if (!JSValueIsObjectOfClass(context, _this, Instance_))
+    if (!CYJSValueIsNSObject(context, _this))
         return NULL;
 
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
     return CYCastJSValue(context, CYJSString(context, CYCastNSCYON(internal->GetValue(), false)));
-} CYCatch }
+} CYCatch(NULL) }
 
 static JSValueRef Instance_callAsFunction_toJSON(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
-    if (!JSValueIsObjectOfClass(context, _this, Instance_))
+    if (!CYJSValueIsNSObject(context, _this))
         return NULL;
 
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
@@ -2376,10 +2555,10 @@ static JSValueRef Instance_callAsFunction_toJSON(JSContextRef context, JSObjectR
         else
             return CYCastJSValue(context, CYJSString(context, [value description]));
     } CYPoolCatch(NULL)
-} CYCatch return /*XXX*/ NULL; }
+} CYCatch(NULL) return /*XXX*/ NULL; }
 
 static JSValueRef Instance_callAsFunction_valueOf(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
-    if (!JSValueIsObjectOfClass(context, _this, Instance_))
+    if (!CYJSValueIsNSObject(context, _this))
         return NULL;
 
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
@@ -2392,37 +2571,56 @@ static JSValueRef Instance_callAsFunction_valueOf(JSContextRef context, JSObject
         return result;
 
     return _this;
-} CYCatch return /*XXX*/ NULL; }
+} CYCatch(NULL) return /*XXX*/ NULL; }
 
 static JSValueRef Instance_callAsFunction_toPointer(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
-    if (!JSValueIsObjectOfClass(context, _this, Instance_))
+    if (!CYJSValueIsNSObject(context, _this))
         return NULL;
 
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
     // XXX: but... but... THIS ISN'T A POINTER! :(
     return CYCastJSValue(context, reinterpret_cast<uintptr_t>(internal->GetValue()));
-} CYCatch return /*XXX*/ NULL; }
+} CYCatch(NULL) return /*XXX*/ NULL; }
 
 static JSValueRef Instance_callAsFunction_toString(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
-    if (!JSValueIsObjectOfClass(context, _this, Instance_))
+    if (!CYJSValueIsNSObject(context, _this))
         return NULL;
 
     Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
     id value(internal->GetValue());
 
-    if (value == nil)
-        return CYCastJSValue(context, "nil");
-
     CYPoolTry {
         // XXX: this seems like a stupid implementation; what if it crashes? why not use the CYONifier backend?
         return CYCastJSValue(context, CYJSString(context, [value description]));
     } CYPoolCatch(NULL)
-} CYCatch return /*XXX*/ NULL; }
+} CYCatch(NULL) return /*XXX*/ NULL; }
+
+static JSValueRef Class_callAsFunction_pointerTo(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
+    if (!CYJSValueIsNSObject(context, _this))
+        return NULL;
+
+    Instance *internal(reinterpret_cast<Instance *>(JSObjectGetPrivate(_this)));
+    id value(internal->GetValue());
+
+    if (!CYIsClass(value))
+        CYThrow("non-Class object cannot be used as Type");
+
+    // XXX: this is a very silly implementation
+
+    std::ostringstream type;
+    type << "@\"";
+    type << class_getName(value);
+    type << "\"";
+
+    CYPoolTry {
+        return CYMakeType(context, type.str().c_str());
+    } CYPoolCatch(NULL)
+} CYCatch(NULL) return /*XXX*/ NULL; }
 
 static JSValueRef Selector_callAsFunction_toString(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     Selector_privateData *internal(reinterpret_cast<Selector_privateData *>(JSObjectGetPrivate(_this)));
     return CYCastJSValue(context, sel_getName(internal->GetValue()));
-} CYCatch }
+} CYCatch(NULL) }
 
 static JSValueRef Selector_callAsFunction_toJSON(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) {
     return Selector_callAsFunction_toString(context, object, _this, count, arguments, exception);
@@ -2436,7 +2634,7 @@ static JSValueRef Selector_callAsFunction_toCYON(JSContextRef context, JSObjectR
         NSString *string([NSString stringWithFormat:@"@selector(%s)", name]);
         return CYCastJSValue(context, CYJSString(context, string));
     } CYPoolCatch(NULL)
-} CYCatch return /*XXX*/ NULL; }
+} CYCatch(NULL) return /*XXX*/ NULL; }
 
 static JSValueRef Selector_callAsFunction_type(JSContextRef context, JSObjectRef object, JSObjectRef _this, size_t count, const JSValueRef arguments[], JSValueRef *exception) { CYTry {
     if (count != 1)
@@ -2452,11 +2650,14 @@ static JSValueRef Selector_callAsFunction_type(JSContextRef context, JSObjectRef
     else
         method = NULL;
 
-    if (const char *type = CYPoolTypeEncoding(pool, context, sel, method))
-        return CYCastJSValue(context, CYJSString(type));
+    const char *encoding(CYPoolTypeEncoding(pool, context, sel, method));
+    if (encoding == NULL)
+        return CYJSNull(context);
 
-    return CYJSNull(context);
-} CYCatch }
+    sig::Signature signature;
+    sig::Parse(pool, &signature, encoding, &Structor_);
+    return CYMakeType(context, &signature);
+} CYCatch(NULL) }
 
 static JSStaticValue Selector_staticValues[2] = {
     {"value", &CYValue_getProperty_value, NULL, kJSPropertyAttributeReadOnly | kJSPropertyAttributeDontDelete},
@@ -2481,6 +2682,11 @@ static JSStaticFunction Instance_staticFunctions[7] = {
     {NULL, NULL, 0}
 };
 
+static JSStaticFunction Class_staticFunctions[2] = {
+    {"pointerTo", &Class_callAsFunction_pointerTo, kJSPropertyAttributeDontEnum | kJSPropertyAttributeDontDelete},
+    {NULL, NULL, 0}
+};
+
 static JSStaticFunction Internal_staticFunctions[2] = {
     {"$cya", &Internal_callAsFunction_$cya, kJSPropertyAttributeDontEnum | kJSPropertyAttributeDontDelete},
     {NULL, NULL, 0}
@@ -2495,7 +2701,7 @@ static JSStaticFunction Selector_staticFunctions[5] = {
 };
 
 #ifdef __APPLE__
-JSValueRef NSCFType$cy$toJSON$inContext$(id self, SEL sel, JSValueRef key, JSContextRef context) { CYObjectiveTry_(context) {
+JSValueRef NSCFType$cy$toJSON$inContext$(id self, SEL sel, JSValueRef key, JSContextRef context) { CYObjectiveTry_ {
     return CYCastJSValue(context, [(NSString *) CFCopyDescription((CFTypeRef) self) autorelease]);
 } CYObjectiveCatch }
 #endif
@@ -2505,11 +2711,17 @@ void CYObjectiveC_Initialize() { /*XXX*/ JSContextRef context(NULL); CYPoolTry {
     $objc_getAssociatedObject = reinterpret_cast<id (*)(id, void *)>(dlsym(RTLD_DEFAULT, "objc_getAssociatedObject"));
     $objc_removeAssociatedObjects = reinterpret_cast<void (*)(id)>(dlsym(RTLD_DEFAULT, "objc_removeAssociatedObjects"));
 
-    apr_pool_t *pool(CYGetGlobalPool());
+    CYPool &pool(CYGetGlobalPool());
 
     Object_type = new(pool) Type_privateData("@");
     Selector_type = new(pool) Type_privateData(":");
 
+    NSArray_ = objc_getClass("NSArray");
+    NSBlock_ = objc_getClass("NSBlock");
+    NSDictionary_ = objc_getClass("NSDictionary");
+    NSString_ = objc_getClass("NSString");
+    Object_ = objc_getClass("Object");
+
 #ifdef __APPLE__
     // XXX: apparently, iOS now has both of these
     NSCFBoolean_ = objc_getClass("__NSCFBoolean");
@@ -2517,19 +2729,18 @@ void CYObjectiveC_Initialize() { /*XXX*/ JSContextRef context(NULL); CYPoolTry {
         NSCFBoolean_ = objc_getClass("NSCFBoolean");
 
     NSCFType_ = objc_getClass("NSCFType");
-    NSGenericDeallocHandler_ = objc_getClass("__NSGenericDeallocHandler");
-    NSMessageBuilder_ = objc_getClass("NSMessageBuilder");
+
     NSZombie_ = objc_getClass("_NSZombie_");
+
+    banned_.insert(Object_);
+    banned_.insert(objc_getClass("__NSAtom"));
+    banned_.insert(objc_getClass("__NSGenericDeallocHandler"));
+    banned_.insert(objc_getClass("NSMessageBuilder"));
+    banned_.insert(objc_getClass("__NSMessageBuilder"));
 #else
     NSBoolNumber_ = objc_getClass("NSBoolNumber");
 #endif
 
-    NSArray_ = objc_getClass("NSArray");
-    NSBlock_ = objc_getClass("NSBlock");
-    NSDictionary_ = objc_getClass("NSDictionary");
-    NSString_ = objc_getClass("NSString");
-    Object_ = objc_getClass("Object");
-
     JSClassDefinition definition;
 
     definition = kJSClassDefinitionEmpty;
@@ -2550,14 +2761,19 @@ void CYObjectiveC_Initialize() { /*XXX*/ JSContextRef context(NULL); CYPoolTry {
     definition.className = "ArrayInstance";
     ArrayInstance_ = JSClassCreate(&definition);
 
+    definition.className = "FunctionInstance";
+    FunctionInstance_ = JSClassCreate(&definition);
+
     definition.className = "ObjectInstance";
     ObjectInstance_ = JSClassCreate(&definition);
 
     definition.className = "StringInstance";
     StringInstance_ = JSClassCreate(&definition);
 
-    definition.className = "FunctionInstance";
-    FunctionInstance_ = JSClassCreate(&definition);
+    definition = kJSClassDefinitionEmpty;
+    definition.className = "Class";
+    definition.staticFunctions = Class_staticFunctions;
+    Class_ = JSClassCreate(&definition);
 
     definition = kJSClassDefinitionEmpty;
     definition.className = "Internal";
@@ -2635,8 +2851,13 @@ void CYObjectiveC_Initialize() { /*XXX*/ JSContextRef context(NULL); CYPoolTry {
     ObjectiveC_Protocols_ = JSClassCreate(&definition);
 
 #ifdef __APPLE__
+// XXX: this is horrible; there has to be a better way to do this
+#ifdef __LP64__
+    class_addMethod(NSCFType_, @selector(cy$toJSON:inContext:), reinterpret_cast<IMP>(&NSCFType$cy$toJSON$inContext$), "^{OpaqueJSValue=}32@0:8@16^{OpaqueJSContext=}24");
+#else
     class_addMethod(NSCFType_, @selector(cy$toJSON:inContext:), reinterpret_cast<IMP>(&NSCFType$cy$toJSON$inContext$), "^{OpaqueJSValue=}16@0:4@8^{OpaqueJSContext=}12");
 #endif
+#endif
 } CYPoolCatch() }
 
 void CYObjectiveC_SetupContext(JSContextRef context) { CYPoolTry {
@@ -2665,6 +2886,7 @@ void CYObjectiveC_SetupContext(JSContextRef context) { CYPoolTry {
     CYSetProperty(context, ObjectiveC, CYJSString("images"), JSObjectMake(context, ObjectiveC_Images_, NULL));
 #endif
 
+    JSObjectRef Class(JSObjectMakeConstructor(context, Class_, NULL));
     JSObjectRef Instance(JSObjectMakeConstructor(context, Instance_, &Instance_new));
     JSObjectRef Message(JSObjectMakeConstructor(context, Message_, NULL));
     JSObjectRef Selector(JSObjectMakeConstructor(context, Selector_, &Selector_new));
@@ -2697,6 +2919,10 @@ void CYObjectiveC_SetupContext(JSContextRef context) { CYPoolTry {
     JSObjectRef String_prototype(CYGetCachedObject(context, CYJSString("String_prototype")));
     JSObjectSetPrototype(context, StringInstance_prototype, String_prototype);
 
+    JSObjectRef Class_prototype(CYCastJSObject(context, CYGetProperty(context, Class, prototype_s)));
+    CYSetProperty(context, cy, CYJSString("Class_prototype"), Class_prototype);
+    JSObjectSetPrototype(context, Class_prototype, Instance_prototype);
+
     CYSetProperty(context, cycript, CYJSString("Instance"), Instance);
     CYSetProperty(context, cycript, CYJSString("Selector"), Selector);
     CYSetProperty(context, cycript, CYJSString("Super"), Super);
@@ -2704,8 +2930,8 @@ void CYObjectiveC_SetupContext(JSContextRef context) { CYPoolTry {
     JSObjectRef box(JSObjectMakeFunctionWithCallback(context, CYJSString("box"), &Instance_box_callAsFunction));
     CYSetProperty(context, Instance, CYJSString("box"), box);
 
-#if defined(__APPLE__) && defined(__arm__) && 0
-    CYSetProperty(context, all, CYJSString("objc_registerClassPair"), &objc_registerClassPair_, kJSPropertyAttributeDontEnum);
+#ifdef __APPLE__
+    CYSetProperty(context, all, CYJSString("choose"), &choose, kJSPropertyAttributeDontEnum);
 #endif
 
     CYSetProperty(context, all, CYJSString("objc_msgSend"), &$objc_msgSend, kJSPropertyAttributeDontEnum);