ÿØÿà JFIF    ÿÛ „  ( %"1!%)+...383,7(-.+  -+++--++++---+-+-----+---------------+---+-++7-----ÿÀ  ß â" ÿÄ     ÿÄ H    !1AQaq"‘¡2B±ÁÑð#R“Ò Tbr‚²á3csƒ’ÂñDS¢³$CÿÄ   ÿÄ %  !1AQa"23‘ÿÚ   ? ôÿ ¨pŸªáÿ —åYõõ\?àÒü©ŠÄï¨pŸªáÿ —åYõõ\?àÓü©ŠÄá 0Ÿªáÿ Ÿå[úƒ ú®ði~TÁbqÐ8OÕpÿ ƒOò¤Oè`–RÂáœá™êi€ßÉ< FtŸI“öÌ8úDf´°å}“¾œ6  öFá°y¥jñÇh†ˆ¢ã/ÃÐ:ªcÈ "Y¡ðÑl>ÿ ”ÏËte:qž\oäŠe÷󲍷˜HT4&ÿ ÓÐü6ö®¿øþßèô Ÿ•7Ñi’•j|“ñì>b…þS?*Óôÿ ÓÐü*h¥£ír¶ü UãSç‚Ÿ[AÐaè[ûª•õ&õj?†Éö+EzP—WeÒírJFt ‘BŒ†Ï‡%#tE Øz ¥OÛ«!1›üä±Í™%ºÍãö]°î(–:@<‹ŒÊö×òÆt¦ãº+‡¦%ÌÁ²h´OƒJŒtMÜ>ÀÜÊw3Y´•牋4ǍýʏTì>œú=Íwhyë,¾Ôò×õ¿ßÊa»«þˆѪQ|%6ž™A õ%:øj<>É—ÿ Å_ˆCbõ¥š±ý¯Ýƒï…¶|RëócÍf溪“t.СøTÿ *Ä¿-{†çàczůŽ_–^XþŒ±miB[X±d 1,é”zEù»& î9gœf™9Ð'.;—™i}!ôšåîqêÛ٤ёý£½ÆA–àôe"A$˝Úsäÿ ÷Û #°xŸëí(l »ý3—¥5m! rt`†0~'j2(]S¦¦kv,ÚÇ l¦øJA£Šƒ J3E8ÙiŽ:cÉžúeZ°€¯\®kÖ(79«Ž:¯X”¾³Š&¡* ….‰Ž(ÜíŸ2¥ª‡×Hi²TF¤ò[¨íÈRëÉ䢍mgÑ.Ÿ<öäS0í„ǹÁU´f#Vß;Õ–…P@3ío<ä-±»Ž.L|kªÀê›fÂ6@»eu‚|ÓaÞÆŸ…¨ááå>åŠ?cKü6ùTÍÆ”†sĤÚ;H2RÚ†õ\Ö·Ÿn'¾ ñ#ºI¤Å´%çÁ­‚â7›‹qT3Iï¨ÖÚ5I7Ë!ÅOóŸ¶øÝñØôת¦$Tcö‘[«Ö³šÒ';Aþ ¸èíg A2Z"i¸vdÄ÷.iõ®§)¿]¤À†–‡É&ä{V¶iŽ”.Ó×Õÿ û?h¬Mt–íª[ÿ Ñÿ ÌV(í}=ibÔ¡›¥¢±b Lô¥‡piη_Z<‡z§èŒ)iÖwiÇ 2hÙ3·=’d÷8éŽ1¦¸c¤µ€7›7Ø ð\á)} ¹fËí›pAÃL%âc2 í§æQz¿;T8sæ°qø)QFMð‰XŒÂ±N¢aF¨…8¯!U  Z©RÊ ÖPVÄÀÍin™Ì-GˆªÅËŠ›•zË}º±ŽÍFò¹}Uw×#ä5B¤{î}Ð<ÙD é©¤&‡ïDbàÁôMÁ." ¤‡ú*õ'VŽ|¼´Úgllº¼klz[Æüï÷Aób‡Eÿ dÑ»Xx9ÃÜ£ÁT/`¼¸vI±Ýµ·Ë‚“G³þ*Ÿû´r|*}<¨îºœ @¦mÄ’M¹”.œ«Y–|6ÏU¤jç¥ÕÞqO ˜kDÆÁ¨5ÿ š;Њ¦¦€GÙk \ –Þ=â¼=SͧµªS°ÚÍpÜãQűÀõ¬?ÃÁ1Ñ•õZà?hóœ€ L¦l{Y*K˜Ù›zc˜–ˆâ ø+¾ ­-Ök¥%ùEÜA'}ˆ><ÊIè“bpÍ/qÞâvoX€w,\úªò6Z[XdÒæ­@Ö—€$òJí#é>'°Ú ôª˜<)4ryÙ£|óAÅn5žêŸyÒäMÝ2{"}‰–¤l÷ûWX\l¾Á¸góÉOÔ /óñB¤f¸çñ[.P˜ZsÊË*ßT܈§QN¢’¡¨§V¼(Üù*eÕ“”5T¨‹Âê¥FŒã½Dü[8'Ò¥a…Ú¶k7a *•›¼'Ò·\8¨ª\@\õ¢¦íq+DÙrmÎ…_ªæ»ŠÓœ¡¯’Ré9MÅ×D™lælffc+ŒÑ,ý™ÿ ¯þǤ=Å’Á7µ÷ÚÛ/“Ü€ñýã¼àí¾ÕÑ+ƒ,uµMâÀÄbm:ÒÎPæ{˜Gz[ƒ¯«® KHà`ßØŠéí¯P8Aq.C‰ à€kòpj´kN¶qô€…Õ,ÜNŠª-­{Zö’æû44‰sŽè‰îVíRœÕm" 6?³D9¡ÇTíÅꋇ`4«¸ÝÁô ï’ýorqКÇZ«x4Žâéþuïf¹µö[P ,Q£éaX±`PÉÍZ ¸äYúg üAx ’6Lê‚xÝÓ*äQ  Ï’¨hÍ =²,6ï#rÃ<¯–£»ƒ‹,–ê•€ aÛsñ'%Æ"®ÛüìBᝠHÚ3ß°©$“XnœÖ’î2ËTeûìxîß ¦å¿çÉ ðK§þ{‘t‚Ϋ¬jéîZ[ ”š7L¥4VÚCE×]m¤Øy”ä4-dz£œ§¸x.*ãÊÊ b÷•h:©‡¦s`BTÁRû¾g⻩‹jø sF¢àJøFl‘È•Xᓁà~*j¯ +(ÚÕ6-£¯÷GŠØy‚<Ç’.F‹Hœw(+)ÜÜâÈzÄäT§FߘãÏ;DmVœ3Àu@mÚüXÝü•3B¨òÌÁÛ<·ÃÜ z,Ì@õÅ·d2]ü8s÷IôÞ¯^Ç9¢u„~ëAŸï4«M? 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Where a `Local` handle only lives as long as the `HandleScope` in which it was allocated, a `Persistent` handle remains valid until it is explicitly disposed. Due to the evolution of the V8 API, it is necessary for NAN to provide a wrapper implementation of the `Persistent` classes to supply compatibility across the V8 versions supported. - Nan::PersistentBase & v8::PersistentBase - Nan::NonCopyablePersistentTraits & v8::NonCopyablePersistentTraits - Nan::CopyablePersistentTraits & v8::CopyablePersistentTraits - Nan::Persistent - Nan::Global - Nan::WeakCallbackInfo - Nan::WeakCallbackType Also see the V8 Embedders Guide section on [Handles and Garbage Collection](https://developers.google.com/v8/embed#handles). ### Nan::PersistentBase & v8::PersistentBase A persistent handle contains a reference to a storage cell in V8 which holds an object value and which is updated by the garbage collector whenever the object is moved. A new storage cell can be created using the constructor or `Nan::PersistentBase::Reset()`. Existing handles can be disposed using an argument-less `Nan::PersistentBase::Reset()`. Definition: _(note: this is implemented as `Nan::PersistentBase` for older versions of V8 and the native `v8::PersistentBase` is used for newer versions of V8)_ ```c++ template class PersistentBase { public: /** * If non-empty, destroy the underlying storage cell */ void Reset(); /** * If non-empty, destroy the underlying storage cell and create a new one with * the contents of another if it is also non-empty */ template void Reset(const v8::Local &other); /** * If non-empty, destroy the underlying storage cell and create a new one with * the contents of another if it is also non-empty */ template void Reset(const PersistentBase &other); /** Returns true if the handle is empty. */ bool IsEmpty() const; /** * If non-empty, destroy the underlying storage cell * IsEmpty() will return true after this call. */ void Empty(); template bool operator==(const PersistentBase &that); template bool operator==(const v8::Local &that); template bool operator!=(const PersistentBase &that); template bool operator!=(const v8::Local &that); /** * Install a finalization callback on this object. * NOTE: There is no guarantee as to *when* or even *if* the callback is * invoked. The invocation is performed solely on a best effort basis. * As always, GC-based finalization should *not* be relied upon for any * critical form of resource management! At the moment you can either * specify a parameter for the callback or the location of two internal * fields in the dying object. */ template void SetWeak(P *parameter, typename WeakCallbackInfo

::Callback callback, WeakCallbackType type); void ClearWeak(); /** * Marks the reference to this object independent. Garbage collector is free * to ignore any object groups containing this object. Weak callback for an * independent handle should not assume that it will be preceded by a global * GC prologue callback or followed by a global GC epilogue callback. */ void MarkIndependent() const; bool IsIndependent() const; /** Checks if the handle holds the only reference to an object. */ bool IsNearDeath() const; /** Returns true if the handle's reference is weak. */ bool IsWeak() const }; ``` See the V8 documentation for [`PersistentBase`](https://v8docs.nodesource.com/node-8.16/d4/dca/classv8_1_1_persistent_base.html) for further information. **Tip:** To get a `v8::Local` reference to the original object back from a `PersistentBase` or `Persistent` object: ```c++ v8::Local object = Nan::New(persistent); ``` ### Nan::NonCopyablePersistentTraits & v8::NonCopyablePersistentTraits Default traits for `Nan::Persistent`. This class does not allow use of the a copy constructor or assignment operator. At present `kResetInDestructor` is not set, but that will change in a future version. Definition: _(note: this is implemented as `Nan::NonCopyablePersistentTraits` for older versions of V8 and the native `v8::NonCopyablePersistentTraits` is used for newer versions of V8)_ ```c++ template class NonCopyablePersistentTraits { public: typedef Persistent > NonCopyablePersistent; static const bool kResetInDestructor = false; template static void Copy(const Persistent &source, NonCopyablePersistent *dest); template static void Uncompilable(); }; ``` See the V8 documentation for [`NonCopyablePersistentTraits`](https://v8docs.nodesource.com/node-8.16/de/d73/classv8_1_1_non_copyable_persistent_traits.html) for further information. ### Nan::CopyablePersistentTraits & v8::CopyablePersistentTraits A helper class of traits to allow copying and assignment of `Persistent`. This will clone the contents of storage cell, but not any of the flags, etc.. Definition: _(note: this is implemented as `Nan::CopyablePersistentTraits` for older versions of V8 and the native `v8::NonCopyablePersistentTraits` is used for newer versions of V8)_ ```c++ template class CopyablePersistentTraits { public: typedef Persistent > CopyablePersistent; static const bool kResetInDestructor = true; template static void Copy(const Persistent &source, CopyablePersistent *dest); }; ``` See the V8 documentation for [`CopyablePersistentTraits`](https://v8docs.nodesource.com/node-8.16/da/d5c/structv8_1_1_copyable_persistent_traits.html) for further information. ### Nan::Persistent A type of `PersistentBase` which allows copy and assignment. Copy, assignment and destructor behavior is controlled by the traits class `M`. Definition: ```c++ template > class Persistent; template class Persistent : public PersistentBase { public: /** * A Persistent with no storage cell. */ Persistent(); /** * Construct a Persistent from a v8::Local. When the v8::Local is non-empty, a * new storage cell is created pointing to the same object, and no flags are * set. */ template Persistent(v8::Local that); /** * Construct a Persistent from a Persistent. When the Persistent is non-empty, * a new storage cell is created pointing to the same object, and no flags are * set. */ Persistent(const Persistent &that); /** * The copy constructors and assignment operator create a Persistent exactly * as the Persistent constructor, but the Copy function from the traits class * is called, allowing the setting of flags based on the copied Persistent. */ Persistent &operator=(const Persistent &that); template Persistent &operator=(const Persistent &that); /** * The destructor will dispose the Persistent based on the kResetInDestructor * flags in the traits class. Since not calling dispose can result in a * memory leak, it is recommended to always set this flag. */ ~Persistent(); }; ``` See the V8 documentation for [`Persistent`](https://v8docs.nodesource.com/node-8.16/d2/d78/classv8_1_1_persistent.html) for further information. ### Nan::Global A type of `PersistentBase` which has move semantics. ```c++ template class Global : public PersistentBase { public: /** * A Global with no storage cell. */ Global(); /** * Construct a Global from a v8::Local. When the v8::Local is non-empty, a new * storage cell is created pointing to the same object, and no flags are set. */ template Global(v8::Local that); /** * Construct a Global from a PersistentBase. When the Persistent is non-empty, * a new storage cell is created pointing to the same object, and no flags are * set. */ template Global(const PersistentBase &that); /** * Pass allows returning globals from functions, etc. */ Global Pass(); }; ``` See the V8 documentation for [`Global`](https://v8docs.nodesource.com/node-8.16/d5/d40/classv8_1_1_global.html) for further information. ### Nan::WeakCallbackInfo `Nan::WeakCallbackInfo` is used as an argument when setting a persistent reference as weak. You may need to free any external resources attached to the object. It is a mirror of `v8:WeakCallbackInfo` as found in newer versions of V8. Definition: ```c++ template class WeakCallbackInfo { public: typedef void (*Callback)(const WeakCallbackInfo& data); v8::Isolate *GetIsolate() const; /** * Get the parameter that was associated with the weak handle. */ T *GetParameter() const; /** * Get pointer from internal field, index can be 0 or 1. */ void *GetInternalField(int index) const; }; ``` Example usage: ```c++ void weakCallback(const WeakCallbackInfo &data) { int *parameter = data.GetParameter(); delete parameter; } Persistent obj; int *data = new int(0); obj.SetWeak(data, callback, WeakCallbackType::kParameter); ``` See the V8 documentation for [`WeakCallbackInfo`](https://v8docs.nodesource.com/node-8.16/d8/d06/classv8_1_1_weak_callback_info.html) for further information. ### Nan::WeakCallbackType Represents the type of a weak callback. A weak callback of type `kParameter` makes the supplied parameter to `Nan::PersistentBase::SetWeak` available through `WeakCallbackInfo::GetParameter`. A weak callback of type `kInternalFields` uses up to two internal fields at indices 0 and 1 on the `Nan::PersistentBase` being made weak. Note that only `v8::Object`s and derivatives can have internal fields. Definition: ```c++ enum class WeakCallbackType { kParameter, kInternalFields }; ```